Question

A sum of money invested at the compound interest payable yearly has interest in

Answer 1

Answer:

49% and 30% respectively

Step-by-step explanation:

Step one:

Given data

Principal =  Rs. 4,200

Final Amount= Rs. 9282 respectively

time = 2 years and

time = 4 years

Required

The rate of interest for 2 and 4 years

Step two:

the compound interest formula is

A= P(1+r)^t

for 2 years

Substitute

$9282= 4200(1+r)^2\\\\9282/4200= (1+r)^2$

$1+r= \sqrt{\frac{9282}{ 4200} }\\\\1+r= \sqrt{2.21} \\\\1+r= 1.49\\\\r=1.49-1\\\\r= 0.49$

the rate is 49%

For 4 years we have

$9282= 4200(1+r)^4\\\\9282/4200= (1+r)^4$

$1+r= \sqrt[4]{\frac{9282}{4500} } \\\\1+r=\sqrt[4]{2.21} \\\\1+r= 1.30\\\\r=1.30-1\\\\r= 0.30$

the rate is 30%