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Back to Simple Interest — Problem 3 · Task Set 1

Exercises: Simple Interest

Show your work for each problem. Round dollar amounts to the nearest cent where needed.

Grade 7·22 problems·~30 min·Common Core Math - Percents·lesson·lesson-simple-interest
Work through problems with immediate feedback
A

Practice: Applying I = Prt

Use the simple interest formula I=PrtI = Prt to find the interest.

1.

Complete the calculation for I=PrtI = Prt where P=$400P = \text{\char"0024}400, r=6%r = 6\%, t=4t = 4 years.

Step 1: Convert rate to decimal: r=r =   ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲  

Step 2: I=400×I = 400 \times   ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲   ×4=\times 4 =   ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲  

r as decimal:
r in formula:
I: