Simple Interest Rate Find
Example:-
Carter Fenton wants to borrow 8000 from Christine O’Brien. He is willing to pay back 8380 in 6 months. What interest rate will he pay?
Solution:-
Use the formula for future value, with A = 8380, P = 8000, t = 
= .5, and solve for r.
A = P(1 + rt)
8380 = 8000(1 + .5r)
8380 = 8000 + 4000r (Distributive property)
380 = 4000r (Subtract 8000)
r = .095
Thus, the interest rate is 9.5%