18,000 amounts to 21,600 in 4 years at simple interest. find the sum of
money that will amount to 25,500 in 5 years, at the same rate of interest.

Step-by-step explanation:

we know that

The simple interest formula is equal to

where

A is the Final Investment Value

P is the Principal amount of money to be invested

r is the rate of interest  

t is Number of Time Periods

step 1

Find the rate of interest

in this problem we have

substitute in the formula above and solve for r

The rate of interest is

step 2

Find the sum of  money that will amount to 25,500 in 5 years, at the same rate of interest

in this part we have

substitute in the formula above and solve for P