Interest earned to the nearest cent for each principal interest rate and time 640$,3%,2 years

If it's a simple interest = $38.4

If it's a compound interest = $678.98

Solutions

Simple interest, I = principal x rate x time

Principal = $640

Time = 2 years

Rate = 3% = 3/100 = 0.03, then substitute respectively.

Compound interest, A = P (1 + r) ^t

Substitute respectively. Remember, always divide your rate in percent by 100.

Don't forget to read the question and approximate correctly.