Jake earned $430 in interest on a $2500 investment after 18 months. What was the annual interest rate? (round to the nearest whole percent)

I=PRT

I=interest

P=principal=investment

R=rate in decimal

T=time in years

remember 12 months per year

given

I=430

P=2500

R=?

T=18/12 years=1.5years

430=2500 times r times 1.5

430=3750r

divide both sides by 430

0.1146666=r

11.4666%

11%

17% interest rate will give you 425 dollars