Question

A sum of money is invested at compound interest payable annually the interest in two successive years is 225 amd 240 find interest earned in the third year



plz solve ​

Answer 1

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Amount after 1 year = A = P (1 +r/100)^1 = P (1 + r/100)
Interest = P r /100 = 225
=> P r = 22,500 --- equation 1

Amount after 2 years = B = P(1+r/100)^2 = A (1 + r/100)
Interest during 2nd year = B - A = A r /100 = 240
A r = 24 000 -- equation 2
Hence P (1 + r/100) r = 24 000, now substitute Pr from equation 1
(1 + r/100 ) = 24 000 / 22 500
r /100 = 0.0667
r = 6.67 % per annum

P = 22 500 / r = Rs 3, 375

amount after 1 year = Rs 3 600
amount after 2 nd year = Rs 3, 840