Question

A sum of money placed at compound intrest doubles itself in 5 yr. It will amount to eight times itself at the same rate of intrest in; a. 7 yr; b. 10 yr; c. 15 yr; d. 20 yr

Answer 1

Answer:

Rs. 800

Brainly Solutions:

Using formula of compound interst

A= P(1+i)^n , here this formula can’t be usefull

so thinking it wisely , in 5 years amount of Rs 100 become 200

then in next 5 years it would be 400 rs

and last 5 years it is rs 800

and this is our answer (5+5+5) = 15

Answer 2

heya...

✔here is ua answer:

n2=8 =2^3

n1=2(doubles)

t2=? (we have to find)

t1=5

Applying this in formula

2^3=2^(t2/5)………2 cancelled each other

3=t2/5

t2= 15(answer)

So option c is correct..

hope it helps..!!❤