Q11 of 52 Page 112

Let us write by calculating the difference between compound interest and simple interest on ₹10,000 for 3 years at 5% per annum.

Let principal = ₹x


∴ Simple interest at 5% for 3 years



= ₹0.15x


At the rate of 5% compound interest per the annum the amount for 3 years



= ₹1.157x


∴ Compound interest for 3 years = 1.157x – x = 0.157x


By the condition, 0.157x – 0.15x = 10000


⇒ 0.007x = 10000


∴ x = 1428571.42


∴ Principal is ₹1428571.42


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