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Home > MC2 > Chapter 9 > Lesson 9.3.1 > Problem 9-75


Sasha saved $850 from her summer job last summer. She put it in an account that earns simple interest each month. After 9 months, her account is worth $1003. What percent interest did she earn each month? Homework Help ✎

Find the amount of money Sasha gained over the 9 months (the interest).

$1003 − $850 = $153

Use the equation I = Prt, where I is the interest, P is the principle (original amount she had), r is the rate (percent interest per month), and t is the time (number of months that have passed).

153 = (850) r (9) Solve for r.

2% interest