Simple interest is calculated with the following formula: S.I. = P × R × T, where P = Principal, R = Rate of Interest in % per annum, and T = Time, usually calculated as the number of years. The rate of interest is in percentage r% and is to be written as r/100.
The intrest will be 15,000×15% × 1
= 2,250
the final amount in her account will be 15000+ 2,250 = 17,250