Question

14. In how much time will a sum of money double if invested at the rate of 8% simple interest per
annum?​

Answer 1

Let sum of money=Rs. x

Therefore amount=Rs. 2x

Interest=sum∗time∗R/100

=x∗time∗8/100

=8x∗time/100

Amount=sum+interest

2x=x+8x∗time/100

2x=100x+8x∗time/100

200x=100x+8x∗time

100x=8x∗time

time=100x.

time=12.5years.