Question

If a sum of money doubles itself in 6 years at simple rate of interest . In how many years it will becomes 8 times ?

(a) 14 yrs
(b) 21 yrs
(c) 49 yrs
(d) 42 yrs

Please Give Full Solution​

Answer 1

Answer:

answer is 49 years

Step-by-step explanation:

let the principal be x

then amount after 6 years = 2x

therefore, simple interest=amount-principle=2x-x=x

rate per annum=s.i*100/p*t=x*100/x*6=16.67%

The amount to become 8 times more, means Interst part should be 8 times and future amount should be 1+8=9 times

9 = 1 x (1 + 16.67% N)

N = 8 / 16.67%

N = 48 years.

In present case, the interest is simple and it is not cumulative.

Answer 2

Answer:

here is your answer...