Question

I keep getting the same answer and I know I am using the right formula.

don't know where I am going wrong.

Answer 1

From March 10 to May 12 = 63 days.

63 days / 365 days = 0.1726 years.

Simple interest formula = Interest = Principal X interest rate x time

Interest = 15305.50 - 15000 = 305.50

Principal = 15000

Time = 0.1726 years

Replace the values into the formula:

305.50 = 15000 x Interest rate x 0.1726

Simplify:

305.50 = 2589.041 x interest rate

Solve for interest rate:

interest rate = 305.50 / 2589.041

interest rate = 0.11799 x 100

Rate = 11.80%