Financial Analysis puzzles, solved step by step
- Puzzles
- 100
- Traced to a firm
- 47
- Topics
- 13
- Hard
- 30
085A company writes off Rs 20 crore of obsolete inventory in full, at a 25% tax rate. Walk the three statements. Then, next year, the same stock is sold for scrap at Rs 5 crore: what happens to that year's gross margin, and why?Big FourCorporate FP&A
Try it first
In the year of the write-down, what happens to cash from operations?
Show the worked solution
Year one: profit falls Rs 15 crore, inventory falls Rs 20 crore, cash rises Rs 5 crore from tax saved. Year two: gross margin is flattered. The scrapped stock sits on the books at zero, so the Rs 5 crore sale is pure gross profit, lifting margin from 30.0% to 30.9% on these figures. The write-down moved profit between years, because it wrote off more than the stock turned out to be worth.
How does a write-down move through the three statements?
Suppose you bought Rs 20,000 of winter jackets for your shop two years ago, and they are now unsellable. Admitting it does not take any money out of your till today; the money left when you bought them. An inventory write-down is a non-cash expense that recognises a loss of value already suffered, so its only cash effect is the tax it saves.
Statement Line Year 1, Rs crore Income statement Cost of goods sold (write-down) +20.0 Income statement Tax at 25% -5.0 Income statement Net income -15.0 Cash flow Net income -15.0 Cash flow Add back non-cash write-down +20.0 Cash flow Cash from operations +5.0 Balance sheet Inventory -20.0 Balance sheet Cash +5.0 Balance sheet Retained earnings -15.0 Year one: assets fall Rs 15 crore (inventory -20, cash +5) and equity falls Rs 15 crore, so the balance sheet balances. Assumes the write-down is tax deductible when booked; confirm the rule in your jurisdiction. Check the balance sheet: assets are down Rs 15 crore, Rs 20 crore of stock gone and Rs 5 crore of cash added, and retained earnings are down by the same Rs 15 crore. It balances, which is the test an interviewer listens for.
Why does next year's gross margin look better than normal?
The stock now has a book value of zero. When it is sold for Rs 5 crore, revenue rises Rs 5 crore and cost of goods sold rises by nothing, because there is no cost left to expense. On a normal Rs 400 crore of sales at 30%, the write-down year shows 25.0% and the scrap year 30.9%. Writing down more than the stock is finally worth pulls a loss into this year and pushes an equal gain into the next.
Gross margin drops to 25.0% in the write-down year and rises to 30.9% when the zero-value stock sells for scrap, while across both years profit after tax totals minus Rs 11.25 crore, exactly the true loss after tax. Over both years nothing is lost or gained by the timing. Pre-tax, the total is minus Rs 20 crore plus Rs 5 crore, or minus Rs 15 crore: the true economic loss on stock that cost Rs 20 crore and fetched Rs 5 crore. Accounting rules generally require inventory to be carried at the lower of cost and net realisable value. If the company expected Rs 5 crore of scrap value, the honest write-down was Rs 15 crore, and the sale would have produced no gain at all.
What does an analyst do with this?
Treat both effects as one event. Strip the write-down out of year one's gross margin and the scrap gain out of year two's, and you see the business's real run-rate margin of 30%. A large write-down followed by margins above the old normal is a pattern worth asking management about, because over-provisioning creates a reserve that can be released into later profits. That is not proof of anything; obsolete stock genuinely varies in what it fetches. It is a question to ask.
Where candidates lose it
The common error is saying cash falls by Rs 20 crore, or by Rs 15 crore, in the write-down year. The cash left when the stock was bought. The write-down is added back on the cash flow statement, and the only cash effect is the Rs 5 crore of tax saved.
The second loss is missing the follow-on. Candidates walk year one cleanly and then say the scrap sale is 'just revenue'. It is revenue with no cost attached, because the cost was already expensed, and that is why the margin jumps. Connecting the two years is the point of the question.
What the interviewer asks next
- How would the answer change if the tax authority allowed the deduction only when the stock is actually disposed of?
- Where in the accounts would you look to see how large the inventory provision is and how it moved?
- Walk the three statements if instead the stock is sold for Rs 25 crore.
087You lend to 10 borrowers. Each has a 2% chance of defaulting over the year, independently of the others. What is the chance that at least one defaults, and what is the expected number of defaults?Rating agenciesBank credit
Try it first
What is the chance that at least one of the ten defaults?
Show the worked solution
The chance of at least one default is 18.3%, and the expected number of defaults is 0.2. Work from the complement: each loan survives with probability 98%, so all ten survive with probability 0.98^10 = 81.7%, and at least one default is the rest. The expected number is simply 10 x 2% = 0.2, which holds whether or not the loans are independent. Independence matters for the first answer, not the second.
Why work from the chance that nothing happens?
Ask what the chance is that at least one of ten friends is late for dinner, each being late one time in fifty. Counting the ways someone could be late is messy: one late, two late, any combination. Counting the single way nobody is late is easy: everyone on time. 'At least one' is one minus 'none', and 'none' for independent events is just the single probabilities multiplied. Each loan survives with probability 0.98, so all ten survive with probability 0.98^10.
To do 0.98^10 in your head, use the shortcut that (1 minus x) to the power n is close to 1 minus nx plus a correction of n(n minus 1)/2 times x squared: 1 minus 0.20 plus 45 x 0.0004 = 0.818. The exact figure is 0.8171, so the chance of at least one default is 18.29%. A second check is the Poisson shortcut, 1 minus e to the minus 0.2, which gives 18.1%.
With ten independent loans each carrying a 2% default chance, no default happens 81.7% of the time, so at least one default happens 18.3% of the time, while expected defaults are 0.2 whether the loans are independent or perfectly linked. Why is the expected number so much simpler?
Expected values add, always. Each loan contributes 0.02 expected defaults, and ten loans contribute 0.2. The expected number of defaults is 0.2 regardless of how the loans are connected, because the expectation of a sum is the sum of the expectations even when the events are correlated. The distribution behind it is lopsided: 81.7% of the time nothing happens, 16.7% of the time exactly one loan fails, and two or more fail 1.6% of the time.
What does correlation change?
Take the extreme. If all ten borrowers are suppliers to one factory and fail together or survive together, there is a 2% chance that all ten default and a 98% chance that none does. Expected defaults are still 0.2. But the chance of at least one default falls to 2%, and the chance of losing the entire book jumps from practically zero to 2%. Correlation does not change the average loss; it moves probability from many small losses into rare large ones, which is the loss a lender cannot survive. That is why credit portfolio work spends its effort on concentration and correlation rather than on the average default rate, and why a portfolio of ten loans to one industry is riskier than its expected loss suggests.
Where candidates lose it
The fast wrong answer is 20%: ten loans times 2%. Adding probabilities only works for events that cannot happen together, and two loans can both default. The error is small here, 20% against 18.3%, but it grows quickly: with 100 such loans the same method gives 200%, which is impossible.
The second loss is giving 18.3% and stopping. The question says independently for a reason. Saying what correlation would do, same expected defaults, fatter tail, is the part a credit interviewer is listening for.
What the interviewer asks next
- How many such loans do you need before at least one default is more likely than not?
- If each loan is Rs 10 crore and recovers 40% on default, what is the expected loss on the book?
- Two of the ten borrowers are in the same group of companies. Does the chance of at least one default go up or down?
088A distributor's inventory rose 20% in rupees over the year, yet its inventory days fell from 60 to 50. What must have happened to cost of goods sold?Corporate FP&ACost accounting
Try it first
By how much must cost of goods sold have grown?
Show the worked solution
Cost of goods sold must have grown about 44%. Inventory days are inventory divided by daily cost of goods sold. For days to fall by a sixth while inventory rises a fifth, the denominator must grow by 1.2 x 60 / 50 = 1.44 times. So the larger stock is serving a much larger business, and is leaner relative to it. Had days stayed at 60, the distributor would be holding Rs 28.8 crore more stock in this example.
How can a bigger stock be leaner?
A kirana shop keeps Rs 60,000 of stock and sells Rs 1,000 a day at cost: two months of cover. A year later it keeps Rs 72,000 and sells Rs 1,440 a day: fifty days of cover. The shelf is fuller, yet each rupee of stock waits less time to be sold. Inventory days measure how long stock waits, not how much there is, so a larger rupee stock can still be leaner if what it serves grew faster.
The relationshipInventory the stock held at the balance sheet date COGS cost of goods sold over the year Days inventory days, how long the stock would last at the current rate of sale What it says in wordsThe growth in cost of goods sold equals the growth in inventory times the ratio of old days to new days.Put rupees on it. Last year: COGS of Rs 730 crore is Rs 2.0 crore a day, and Rs 120 crore of stock is 60 days of it. This year inventory is Rs 144 crore. For that to be 50 days, daily COGS must be Rs 2.88 crore, an annual Rs 1,051.2 crore, up 44%.
Inventory grew 20% while cost of goods sold grew 44%, so stock fell from 60 to 50 days of cover, and at the old 60 days the distributor would hold Rs 28.8 crore more inventory. What is the cash meaning of the change?
Compare the stock with what it would have been at the old turn. At 60 days, this year's cost of goods sold would need Rs 172.8 crore of inventory. The distributor holds Rs 144 crore. The faster turn means Rs 28.8 crore less cash tied up in stock than the business would otherwise need, even though the balance sheet shows inventory up Rs 24 crore. An analyst who reads only the rupee change calls this a working capital problem; the ratio says it is a working capital improvement.
What would make you distrust the 50 days?
Three checks. Year-end timing: inventory is a snapshot, and a stock-light last week of March can flatter the ratio; average inventory over the year is a better numerator. The denominator: some analysts compute days on revenue, not COGS, and mixing the two across years breaks the comparison. And mix: if the growth came from a fast-moving new product line, the old lines may be turning as slowly as ever. The ratio summarises; it does not explain.
Where candidates lose it
The common slip is adding instead of multiplying: inventory up 20%, days down about 17%, so COGS up about 37%. Ratios combine through their growth factors, 1.2 times 1.2, which gives 44%. The additive shortcut drifts further the bigger the moves.
The second loss is reading the rupee rise in inventory as bad news. The question is built to see whether you look past the level to the rate: more stock, held for less time, against much higher sales. Say what cash the faster turn saved.
What the interviewer asks next
- Inventory fell 10% while days rose from 45 to 60. What happened to cost of goods sold?
- Why might average inventory give a different answer from closing inventory here?
- How would you split the change in inventory into a part from growth and a part from efficiency?
089A company's revenue is Rs 1,000 crore in both years. Its EBITDA margin rises from 18% to 20%, while its EBIT margin falls from 12% to 11%. What must have happened to depreciation and amortisation, in rupees, and what could explain it?Corporate FP&AEquity research
Try it first
By how much did depreciation and amortisation change?
Show the worked solution
Depreciation and amortisation rose from Rs 60 crore to Rs 90 crore, up Rs 30 crore or half again. D&A is exactly the gap between EBITDA and EBIT: 180 minus 120 last year, 200 minus 110 this year. The usual causes are a burst of capex now being depreciated, an acquisition bringing amortisation of intangibles, or an accounting change, such as lease accounting, that moves a cash cost out of operating expenses and into depreciation.
How do you find D&A from two margins?
If your take-home pay rises but your savings fall, something between the two lines got bigger: rent, EMI, school fees. You find it by looking at the gap, not the lines. EBITDA and EBIT differ by exactly one thing, depreciation and amortisation, so when the two margins move in opposite directions, D&A has grown by the sum of the two moves. Here, 2 points up and 1 point down is 3 points of Rs 1,000 crore of revenue, or Rs 30 crore.
Convert to rupees to be sure. EBITDA is Rs 180 crore last year and Rs 200 crore this year; EBIT is Rs 120 crore and Rs 110 crore. D&A is Rs 60 crore, then Rs 90 crore. Revenue is flat, so D&A went from 6% to 9% of revenue.
On flat revenue of Rs 1,000 crore, EBITDA rose Rs 20 crore while EBIT fell Rs 10 crore, so depreciation and amortisation must have risen Rs 30 crore, from Rs 60 crore to Rs 90 crore. What could explain a 50% jump in D&A on flat revenue?
Three stories, each with a different meaning. First, a capex burst: a new plant or system has come into use and is being depreciated, but has not yet lifted revenue. That is a timing story, and the question is when revenue arrives. Second, an acquisition: buying a business brings customer lists and brands onto the balance sheet, and amortising them raises D&A without any new cash spend. Third, an accounting change. Under lease accounting standards such as Ind AS 116, rent stops being an operating expense and becomes depreciation plus interest, which raises EBITDA and D&A together without changing the cash the company pays.
The lease story fits the EBITDA rise neatly, since rent leaving operating expenses lifts EBITDA directly. But EBIT usually edges up under that change too, because part of the old rent now sits in interest, below EBIT. EBIT falling here suggests at least some genuine new depreciation as well.
Which margin should an analyst trust?
Neither on its own. EBITDA ignores the cost of the assets that produce the profit, so a company can raise its EBITDA margin simply by buying capacity or by reclassifying rent. EBIT charges for those assets, but through accounting depreciation that may not match their real wear. The honest check is cash: EBITDA less capex less lease payments, compared across both years, tells you whether the business really earns more. Ask management which of the three stories is true before praising the higher EBITDA margin.
Where candidates lose it
The common slip is subtracting the margin changes: 2 points minus 1 point, so D&A rose 1 point, Rs 10 crore. The moves go in opposite directions, so the gap widened by both: 3 points, Rs 30 crore. Working in rupees removes the confusion at once.
The second loss is giving the number without a reason. The interviewer wants a cause, and the strong answer names more than one, capex, acquisition amortisation and lease accounting, and says what each would mean for the cash the business really generates.
What the interviewer asks next
- If the change came entirely from lease accounting, what would you expect to see in interest expense?
- Revenue grew 10% and both margins stayed flat. What happened to D&A in rupees?
- Why do lenders often look at EBITDA less capex rather than EBITDA?
093A perpetuity pays Rs 100 a year forever, discounted at 10%. What share of its present value comes from the first 10 years of payments? From the first 30?Equity researchCorporate finance
Try it first
Roughly what share of the value comes from the first 10 years?
Show the worked solution
About 61% from the first 10 years and 94% from the first 30. The perpetuity is worth Rs 100 / 0.10 = Rs 1,000. Payments beyond year N are themselves a perpetuity, starting later, so their share is 1/1.1^N: 38.6% beyond year 10 and 5.7% beyond year 30. Add growth and the far years matter much more: at 5% growth only 37% of the value arrives in the first decade.
Is there a quick way to split a perpetuity by year?
Suppose you are promised a pension of Rs 100 a year forever. Starting ten years from now, what you are owed is again a Rs 100 perpetuity, worth Rs 1,000 at that date; you just have to wait ten years for it. The value of the payments after year N is the full perpetuity value, discounted back N years, so its share of the total is 1/(1 + r)^N and the first N years take the rest. At 10% that is 1/1.1^10 = 0.386 beyond year 10 and 1/1.1^30 = 0.057 beyond year 30.
The relationshipr the discount rate, 10% g the growth rate of the payment, zero here N the number of years counted What it says in wordsThe share of value received in the first N years is one minus the discount factor for N years, adjusted for growth.In rupees, the first ten years are worth Rs 614 of the Rs 1,000. Half the value arrives in the first 7.3 years, because 1.1 to the power 7.3 is 2. A useful mental marker: at 10%, value halves every seven years or so.
Discounted at 10%, a flat perpetuity delivers 61% of its value in the first 10 years and 94% in 30, but if the payment grows 5% a year only 37% arrives in the first decade, which is why a DCF's terminal value dominates. Why does this matter for a DCF?
A DCF forecasts a company for perhaps ten years and puts everything after into a terminal value. With no growth, the terminal value would already be 39% of the total. Companies are usually assumed to grow, and growth pushes value further out: at 5% growth and a 10% discount rate, the gap between them shrinks to about 4.8% a year, half the value arrives only after 14.9 years, and the terminal value is 63% of the total. Most of a DCF's value sits beyond the explicit forecast, so the terminal growth rate and discount rate deserve more scrutiny than the detail of year three.
The limitation runs the other way too. The terminal value depends on the gap between the discount rate and growth, so a small change in either swings it sharply. Present a DCF with the terminal value's share stated and a sensitivity table beside it, rather than a single number.
Where candidates lose it
The intuitive answer is tiny, because ten years is nothing against forever. It ignores discounting: a payment in year 50 is worth under one hundredth of its face value today. The first decade carries 61% of the value with no growth.
The opposite loss comes in the follow-up. Candidates who learn the 61% conclude that the terminal value is a minor detail. Add realistic growth and the far years matter far more: at 5% growth only 37% of the value sits in the first ten years.
What the interviewer asks next
- At what discount rate would the first 10 years carry 75% of a flat perpetuity's value?
- If a DCF's terminal value is 80% of the enterprise value, what does that tell you about where the risk in the valuation sits?
- How does the share change if the discount rate falls from 10% to 8% with 5% growth?
094A cafe sells coffee at Rs 120 a cup, though each cup costs Rs 140 to serve, to bring people in. Each food item earns Rs 60 of contribution. What share of coffee buyers must also buy a food item for the coffee to pay its way?Corporate FP&ACost accounting
Try it first
What attach rate makes the coffee break even?
Show the worked solution
One coffee buyer in three, 33.3%, must also buy a food item. Each cup loses Rs 20: Rs 140 to serve against Rs 120 of price. Each food item adds Rs 60 of contribution. So one food sale covers the loss on three coffees, and the break-even attach rate is 20 / 60. Two checks matter: only food bought because of the coffee counts, and Rs 140 must be the true extra cost of a cup, not a share of rent.
How do you price a product that loses money on purpose?
A shopkeeper who sells milk below cost does it because people who come in for milk also pick up bread and biscuits. The milk is a door, and its price is justified by what walks through it. A loss leader pays its way when the profit on what customers also buy covers the loss on the leader, so the number to manage is the attach rate. Here, each coffee loses Rs 20 and each food item earns Rs 60.
The relationshipa* the break-even attach rate: share of leader buyers who also buy the add-on contribution price less the variable cost of the add-on What it says in wordsThe break-even attach rate is the loss on the leader divided by the contribution on what it brings in.Three coffees at a Rs 20 loss each balance one food item at Rs 60 of contribution, so the coffee pays its way once one coffee buyer in three also buys food. What makes the one-in-three figure misleading?
Two things. First, only incremental food counts. If half the people buying food would have come in for lunch anyway, their food was not brought in by the cheap coffee, and the coffee cannot claim it. The attach rate that matters is the share of coffee buyers who buy food because they came for coffee, which is lower than the attach rate on the till receipts. Measuring it needs a comparison: a price test in a few outlets, or the behaviour of customers before and after the coffee price changed.
Second, ask what is inside the Rs 140. If it includes a share of rent, staff and the coffee machine, those costs are there whether or not one more cup is sold. Suppose the extra cost of a cup, beans, milk and the cup itself, is Rs 70. Then each coffee contributes Rs 50 at the margin and needs no food to pay its way; it only looks like a loss after fixed costs are spread across it. Decisions about one more sale use contribution; fully loaded cost answers a different question, whether the whole cafe covers its overheads.
What would you track after launch?
Attach rate by time of day, average food contribution per coffee buyer, and the number of new customers the coffee brings in. A cafe that hits 40% attach in the morning and 15% in the afternoon may want the cheap coffee only before noon. The limitation is that habit takes time: a promotion judged on its first two weeks can look worse than it will in month three.
Where candidates lose it
The common slip is setting the attach rate at the point where food covers the full price of the coffee, or dividing the wrong way and getting three food items per coffee. Set the loss per coffee against the gain per food item and it falls out: 20 / 60.
The bigger loss is stopping at a third. The interviewer is waiting for the two questions behind it: is the food sale caused by the coffee, and is Rs 140 really the extra cost of a cup? Either can reverse the conclusion.
What the interviewer asks next
- The cafe raises coffee to Rs 130. What attach rate does it now need?
- Half of the food buyers would have come anyway. What measured attach rate do you need on the till receipts?
- How would you test whether the cheap coffee is bringing in new customers at all?
095Estimate the annual revenue of one multiplex screen in a tier-1 Indian city.Equity researchCorporate finance
Try it first
Which input moves the answer most, and is hardest to guess?
Show the worked solution
Roughly Rs 4.4 crore a year, on the assumptions below. Five shows a day, 200 seats and 30% average occupancy give about 1.1 lakh admissions a year. At an average ticket of Rs 250 that is Rs 2.74 crore; food and beverage at Rs 130 a head adds Rs 1.42 crore; on-screen advertising adds perhaps Rs 0.2 crore. Every input is an assumption to state and then test.
What is the structure before any number?
Estimating what a hall earns is like estimating a restaurant: count the covers, then what each cover spends, then any income that does not depend on covers. Estimate each revenue stream separately: tickets and food both hang off admissions, while advertising depends on the screen, not the audience on the day. So the first job is admissions: shows a day times seats times occupancy times days.
Assume five shows a day on a 200-seat screen, open every day. Occupancy is the soft input: a weekend evening may be nearly full while a Tuesday matinee is mostly empty. Build it rather than guess it: if weekdays run at 20% and weekends at 55%, the weighted average is (5 x 20% + 2 x 55%) / 7, about 30%.
Stream Driver Assumption Rs crore a year Tickets admissions x average ticket 109,500 x Rs 250 2.74 Food and beverage admissions x spend per head 109,500 x Rs 130 1.42 Advertising per screen Rs 20 lakh 0.20 Total 4.36 Every price, occupancy and spend figure is an illustrative assumption, not an industry statistic. About 1.09 lakh admissions a year support Rs 2.74 crore of tickets and Rs 1.42 crore of food and beverage, with advertising a small extra, for about Rs 4.4 crore a year from one screen. How do you know the number is sensible?
Check it three ways. Per day: Rs 4.4 crore over 365 days is about Rs 1.19 lakh, which is 300 admissions spending about Rs 400 each in total, plausible for a screen with five shows. Per seat: about Rs 2.2 lakh a year. And the mix: food at about a third of revenue is the kind of share multiplex operators discuss, and it is high-margin money. The softest input is occupancy: every 10 points on it moves revenue by about Rs 1.4 crore, because it drives tickets and food together.
Say what revenue is not. Gross ticket revenue includes entertainment taxes in some form, and a large share of net ticket income goes to the film's distributor. Confirm current tax rates and typical revenue-sharing terms before using the figure for anything beyond a size estimate. Food, by contrast, the operator keeps in full, which is why its share matters to profit far more than its share of revenue suggests.
Where candidates lose it
The common error is assuming full houses: 5 shows x 200 seats x 365 days at Rs 250 is over Rs 9 crore from tickets alone, more than three times the ticket estimate. Average occupancy across every show, including weekday mornings, is far below a packed Friday night.
The second loss is stopping at tickets. Food and beverage is roughly a third of revenue on these assumptions and a larger share of profit. An interviewer asking about a multiplex wants to hear that you know the business is partly a restaurant with a screen attached.
What the interviewer asks next
- How would a premium recliner screen with 60 seats compare, and why?
- What share of this revenue would you expect the operator to keep after paying the distributor and taxes, and what would you check?
- A new release fills the screen to 70% for two weeks. How much does that add to the year?
