Math problem HELP

Question

Peter deposited a sum of money in SouthEast Bank. The money grew to $1300 in 8 months. SouthEast Bank pays simple interest at the rate of 6% per year. How much did Peter deposit?

Answer 1

the underlying formula that you want to use here is the simple interest formula

A = P(1 + RT)

for the information given in the question we have

1300 = P(1 + 0.06 x 8/12)

P = 1300 / (1 + 0.04)

=1300 / (1.04)

=1250

meaning that Peter's initial deposit was $1250

Answer 2

1300=A

t= 8/12= 2/3 year

6%=.06 = r = annual interest rate

A=P+Prt=P(1+rt)

P=A/(1+r)=1300/(1+.06(2/3))

=1300/1.04

=$1250