Time & moneyAges 13-15

Simple interest & savings

Use I = Prt to calculate simple interest earned on a principal sum over a number of years. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 13-15

Simple interest & savings

Take your time. Show your thinking.

1. $200 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$200 · 5% · 1 · Simple interest & savings
2. $900 is invested at 10% simple interest per year for 5 years. How much simple interest is earned?
$900 · 10% · 5 · Simple interest & savings
3. $400 is invested at 5% simple interest per year for 2 years. How much simple interest is earned?
$400 · 5% · 2 · Simple interest & savings
4. $600 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$600 · 9% · 4 · Simple interest & savings
5. $900 is invested at 9% simple interest per year for 3 years. How much simple interest is earned?
$900 · 9% · 3 · Simple interest & savings
6. $1000 is invested at 10% simple interest per year for 2 years. How much simple interest is earned?
$1000 · 10% · 2 · Simple interest & savings
7. $100 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$100 · 4% · 3 · Simple interest & savings
8. $600 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$600 · 4% · 4 · Simple interest & savings
9. $1100 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$1100 · 7% · 5 · Simple interest & savings
10. $1900 is invested at 2% simple interest per year for 5 years. How much simple interest is earned?
$1900 · 2% · 5 · Simple interest & savings
11. $2000 is invested at 3% simple interest per year for 6 years. How much simple interest is earned?
$2000 · 3% · 6 · Simple interest & savings
12. $2000 is invested at 9% simple interest per year for 5 years. How much simple interest is earned?
$2000 · 9% · 5 · Simple interest & savings

12 questions · Seed 47 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 13-15

Simple interest & savings

Answers and reasoning. Review before teaching.

1. $200 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$10
Simple interest I = P × r × t = $200 × 5% × 1 = $10.
2. $900 is invested at 10% simple interest per year for 5 years. How much simple interest is earned?
$450
Simple interest I = P × r × t = $900 × 10% × 5 = $450.
3. $400 is invested at 5% simple interest per year for 2 years. How much simple interest is earned?
$40
Simple interest I = P × r × t = $400 × 5% × 2 = $40.
4. $600 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$216
Simple interest I = P × r × t = $600 × 9% × 4 = $216.
5. $900 is invested at 9% simple interest per year for 3 years. How much simple interest is earned?
$243
Simple interest I = P × r × t = $900 × 9% × 3 = $243.
6. $1000 is invested at 10% simple interest per year for 2 years. How much simple interest is earned?
$200
Simple interest I = P × r × t = $1000 × 10% × 2 = $200.
7. $100 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$12
Simple interest I = P × r × t = $100 × 4% × 3 = $12.
8. $600 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$96
Simple interest I = P × r × t = $600 × 4% × 4 = $96.
9. $1100 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$385
Simple interest I = P × r × t = $1100 × 7% × 5 = $385.
10. $1900 is invested at 2% simple interest per year for 5 years. How much simple interest is earned?
$190
Simple interest I = P × r × t = $1900 × 2% × 5 = $190.
11. $2000 is invested at 3% simple interest per year for 6 years. How much simple interest is earned?
$360
Simple interest I = P × r × t = $2000 × 3% × 6 = $360.
12. $2000 is invested at 9% simple interest per year for 5 years. How much simple interest is earned?
$900
Simple interest I = P × r × t = $2000 × 9% × 5 = $900.

12 questions · Seed 47 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 13-15

Simple interest & savings

Take your time. Show your thinking.

1. $200 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$200 · 5% · 1 · Simple interest & savings
2. $900 is invested at 10% simple interest per year for 5 years. How much simple interest is earned?
$900 · 10% · 5 · Simple interest & savings
3. $400 is invested at 5% simple interest per year for 2 years. How much simple interest is earned?
$400 · 5% · 2 · Simple interest & savings
4. $600 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$600 · 9% · 4 · Simple interest & savings
5. $900 is invested at 9% simple interest per year for 3 years. How much simple interest is earned?
$900 · 9% · 3 · Simple interest & savings
6. $1000 is invested at 10% simple interest per year for 2 years. How much simple interest is earned?
$1000 · 10% · 2 · Simple interest & savings
7. $100 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$100 · 4% · 3 · Simple interest & savings
8. $600 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$600 · 4% · 4 · Simple interest & savings
9. $1100 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$1100 · 7% · 5 · Simple interest & savings
10. $1900 is invested at 2% simple interest per year for 5 years. How much simple interest is earned?
$1900 · 2% · 5 · Simple interest & savings
11. $2000 is invested at 3% simple interest per year for 6 years. How much simple interest is earned?
$2000 · 3% · 6 · Simple interest & savings
12. $2000 is invested at 9% simple interest per year for 5 years. How much simple interest is earned?
$2000 · 9% · 5 · Simple interest & savings

12 questions · Seed 47 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 13-15

Simple interest & savings

Answers and reasoning. Review before teaching.

1. $200 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$10
Simple interest I = P × r × t = $200 × 5% × 1 = $10.
2. $900 is invested at 10% simple interest per year for 5 years. How much simple interest is earned?
$450
Simple interest I = P × r × t = $900 × 10% × 5 = $450.
3. $400 is invested at 5% simple interest per year for 2 years. How much simple interest is earned?
$40
Simple interest I = P × r × t = $400 × 5% × 2 = $40.
4. $600 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$216
Simple interest I = P × r × t = $600 × 9% × 4 = $216.
5. $900 is invested at 9% simple interest per year for 3 years. How much simple interest is earned?
$243
Simple interest I = P × r × t = $900 × 9% × 3 = $243.
6. $1000 is invested at 10% simple interest per year for 2 years. How much simple interest is earned?
$200
Simple interest I = P × r × t = $1000 × 10% × 2 = $200.
7. $100 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$12
Simple interest I = P × r × t = $100 × 4% × 3 = $12.
8. $600 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$96
Simple interest I = P × r × t = $600 × 4% × 4 = $96.
9. $1100 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$385
Simple interest I = P × r × t = $1100 × 7% × 5 = $385.
10. $1900 is invested at 2% simple interest per year for 5 years. How much simple interest is earned?
$190
Simple interest I = P × r × t = $1900 × 2% × 5 = $190.
11. $2000 is invested at 3% simple interest per year for 6 years. How much simple interest is earned?
$360
Simple interest I = P × r × t = $2000 × 3% × 6 = $360.
12. $2000 is invested at 9% simple interest per year for 5 years. How much simple interest is earned?
$900
Simple interest I = P × r × t = $2000 × 9% × 5 = $900.

12 questions · Seed 47 · Age guidance, not curriculum certification