Slater begins saving for college tuition. He invests $1000 in an account that pays 2.5% simple interest. How many years before his account has reached $1500?

The formula is Interest = principle times rate times time in years.

I=prt

p=1000

r = 0.025

t=x

To find the amount of interest that is earned in a specific time frame, subtract the final amount of money by the principal. 1500-1000=500.

500 = 1000 (0.025) x

500 = 25x

x = 20 years