Question

in how many years will sum of money double itself at 10% per annum

Answer 1

the time in which the sum of money will double itself is 10 years

Answer 2

10 year is the answer.
Let assume p=100
R=10%
T
Si=100
A=200
Si=prt/100
100=100x10xt/100
T=100/10=10 years