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Question
In which of the following situations, do the lists of numbers involved form an AP? Give reasons for your answers
The amount of money in the account of Varun at the end of every year when Rs 1000 is deposited at simple interest of 10% per annum.
Solution
Simple interest = `("Principal" xx "Rate" xx "Time")/100`
= `(1000 xx 10 xx 1)/100`
= 100
So, the amount of money in the account of varun at the end of every year is
1000, (1000 + 100 × 1), (1000 + 100 × 2), (1000 + 100 × 3),...
i.e., 1000, 1100, 1200, 1300,...
Which form an AP, with common difference (d) = 1100 – 1000 = 100
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