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  1. 100Online numerical test style: three divisions had revenue of Rs 420, 260 and 120 crore last year and Rs 462, 299 and 150 crore this year. Which division grew fastest, and which contributed most to the growth in total revenue?Mental maths and countingWarm upBarclaysNew York · 2026

    Try it first

    Which division contributed most to total growth?

    Show the worked solution

    Division C grew fastest, at 25%, but Division A contributed most, adding Rs 42 crore of the Rs 111 crore increase. Growth rates are 42/420 = 10%, 39/260 = 15% and 30/120 = 25%. Rupee increases are 42, 39 and 30. A's slower rate on a much bigger base adds more. Total revenue grew 13.9%, and A supplied 37.8% of that growth.

    Why are these two different questions?

    A child's pocket money rising from 100 to 150 is 50% growth; a parent's salary rising from 1 lakh to 1.1 lakh is 10%. The household budget still cares far more about the salary. A growth rate measures change relative to each part's own size; contribution measures change in rupees, which is what adds up to the total. Online tests ask both in one question because candidates who rush answer the same division twice.

    Two questions, two columns: growth rate and rupee increaseDivisionLast yearThis yearGrowthIncreaseadded by youDivision A42046210%+42Division B26029915%+39Division C12015025%+30Total80091113.9%+111Rs crore. Lime cells answer the two questions asked.1Fastest growth: C, 25%on the smallest base2Biggest contributor: A, +4237.8% of the total rise3Total grew 13.9%not the 16.7% simple average
    Adding a growth column and an increase column to the table shows Division C growing fastest at 25% while Division A adds the most, Rs 42 crore or 37.8% of the Rs 111 crore rise, and total revenue grows 13.9%.

    How do you do it fast under a timer?

    Compute the increases first, because they are subtractions: 42, 39, 30. Then compute rates only where needed, using easy fractions: 42 on 420 is a tenth, 30 on 120 is a quarter, 39 on 260 sits between them at 15%. Write the two added columns next to the table rather than holding the numbers in your head, because the next question in the set often reuses them.

    The relationship
    gtotal=∑iwi gi=420800(10%)+260800(15%)+120800(25%)=13.9%g_{\text{total}} = \sum_i w_i\, g_i = \tfrac{420}{800}(10\%) + \tfrac{260}{800}(15\%) + \tfrac{120}{800}(25\%) = 13.9\%
    w_ieach division's share of last year's revenue
    g_ieach division's growth rate
    What it says in wordsTotal growth is the average of the divisions' growth rates weighted by their starting size.

    That weighting is the third trap a test can set. The simple average of 10%, 15% and 25% is 16.7%, which is wrong because it gives the small division the same say as the large one. Total revenue went from 800 to 911, a rise of 13.9%. If an option shows 16.7%, it is there to catch exactly that shortcut.

    Where candidates lose it

    The trap is answering C to both parts, because the 25% is the most striking number on the page. The test separates fast readers from careful ones by asking for two different measures in one question.

    The second loss is averaging growth rates to get total growth. Always weight by size, or simply add the totals and compute once.

    What the interviewer asks next

    • If Division C keeps growing 25% and A keeps growing 10%, in how many years does C add more rupees than A?
    • What share of total revenue will each division have next year if growth rates repeat?
    • How would you present these numbers on one slide for a client?

    Asked at Barclays, Investment Banking, New York, 2026 (Wall Street Oasis): The numerical section involved interpreting tables and charts quickly