A $5000 investment earns $1575 simple interest in three years. What is the annual interest rate?

a. 1.05%

b. 3.15%

c. 10.5%

d. 31.5%

I=PRT

P=principal

I=interest

R=rate

T=time in years

Principal=5000

Interest=1575

R=?

T=3 years

I=PRT

1575 = (5000) (R) (3)

1575=15000 (R)

divide both sides by 15000

0.105=R

we need to covert to percent

x%=x/100

0.105/1 times 100/100=10.5/100=10.5%

answer is C