Question

A sum of money is investedat compound interest payable annyally.The interest into successive year is rupees 225 and rupees 240. find the original sum

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Answer 1

• Interest at the end of 1 year =275 Rs.

• Interest at the end of 2 years =300 Rs.

• Interest for 1 year =300−275=25 Rs.

Rate of interest =

P×R × T

☆ nterest on Rs.225

for one year =

for one year = Rs. 240 - Rs. 225 = Rs. 15

Rate of interest = 100IPT

=100×15225×1=203%=

623%100IPT=100×15225×1=203%

=623%

Interest on the original sum for one year =

Rs.225

Original sum =

100IRT=100×225203×1100IRT=100×225203×1 = Rs.3375

At the end of two years, total amount = 3375 + 225 + 240

☆ = Rs.3840

Interest for 3rd year =

Interest on Rs.3840 for one year

= 3840×203×11003840×203×1100

= Rs.256