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. $900 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$900 · 9% · 4 · Simple interest & savings
2. $200 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$200 · 5% · 4 · Simple interest & savings
3. $700 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$700 · 4% · 4 · Simple interest & savings
4. $1200 is invested at 4% simple interest per year for 1 year. How much simple interest is earned?
$1200 · 4% · 1 · Simple interest & savings
5. $600 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$600 · 5% · 4 · Simple interest & savings
6. $700 is invested at 5% simple interest per year for 6 years. How much simple interest is earned?
$700 · 5% · 6 · Simple interest & savings
7. $1300 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$1300 · 7% · 1 · Simple interest & savings
8. $1500 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$1500 · 7% · 5 · Simple interest & savings
9. $1800 is invested at 7% simple interest per year for 3 years. How much simple interest is earned?
$1800 · 7% · 3 · Simple interest & savings
10. $700 is invested at 4% simple interest per year for 6 years. How much simple interest is earned?
$700 · 4% · 6 · Simple interest & savings
11. $2000 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$2000 · 7% · 5 · Simple interest & savings
12. $1400 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$1400 · 7% · 1 · Simple interest & savings

12 questions · Seed 54 · 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. $900 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$324
Simple interest I = P × r × t = $900 × 9% × 4 = $324.
2. $200 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$40
Simple interest I = P × r × t = $200 × 5% × 4 = $40.
3. $700 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$112
Simple interest I = P × r × t = $700 × 4% × 4 = $112.
4. $1200 is invested at 4% simple interest per year for 1 year. How much simple interest is earned?
$48
Simple interest I = P × r × t = $1200 × 4% × 1 = $48.
5. $600 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$120
Simple interest I = P × r × t = $600 × 5% × 4 = $120.
6. $700 is invested at 5% simple interest per year for 6 years. How much simple interest is earned?
$210
Simple interest I = P × r × t = $700 × 5% × 6 = $210.
7. $1300 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$91
Simple interest I = P × r × t = $1300 × 7% × 1 = $91.
8. $1500 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$525
Simple interest I = P × r × t = $1500 × 7% × 5 = $525.
9. $1800 is invested at 7% simple interest per year for 3 years. How much simple interest is earned?
$378
Simple interest I = P × r × t = $1800 × 7% × 3 = $378.
10. $700 is invested at 4% simple interest per year for 6 years. How much simple interest is earned?
$168
Simple interest I = P × r × t = $700 × 4% × 6 = $168.
11. $2000 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$700
Simple interest I = P × r × t = $2000 × 7% × 5 = $700.
12. $1400 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$98
Simple interest I = P × r × t = $1400 × 7% × 1 = $98.

12 questions · Seed 54 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 13-15

Simple interest & savings

Take your time. Show your thinking.

1. $900 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$900 · 9% · 4 · Simple interest & savings
2. $200 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$200 · 5% · 4 · Simple interest & savings
3. $700 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$700 · 4% · 4 · Simple interest & savings
4. $1200 is invested at 4% simple interest per year for 1 year. How much simple interest is earned?
$1200 · 4% · 1 · Simple interest & savings
5. $600 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$600 · 5% · 4 · Simple interest & savings
6. $700 is invested at 5% simple interest per year for 6 years. How much simple interest is earned?
$700 · 5% · 6 · Simple interest & savings
7. $1300 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$1300 · 7% · 1 · Simple interest & savings
8. $1500 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$1500 · 7% · 5 · Simple interest & savings
9. $1800 is invested at 7% simple interest per year for 3 years. How much simple interest is earned?
$1800 · 7% · 3 · Simple interest & savings
10. $700 is invested at 4% simple interest per year for 6 years. How much simple interest is earned?
$700 · 4% · 6 · Simple interest & savings
11. $2000 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$2000 · 7% · 5 · Simple interest & savings
12. $1400 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$1400 · 7% · 1 · Simple interest & savings

12 questions · Seed 54 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 13-15

Simple interest & savings

Answers and reasoning. Review before teaching.

1. $900 is invested at 9% simple interest per year for 4 years. How much simple interest is earned?
$324
Simple interest I = P × r × t = $900 × 9% × 4 = $324.
2. $200 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$40
Simple interest I = P × r × t = $200 × 5% × 4 = $40.
3. $700 is invested at 4% simple interest per year for 4 years. How much simple interest is earned?
$112
Simple interest I = P × r × t = $700 × 4% × 4 = $112.
4. $1200 is invested at 4% simple interest per year for 1 year. How much simple interest is earned?
$48
Simple interest I = P × r × t = $1200 × 4% × 1 = $48.
5. $600 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$120
Simple interest I = P × r × t = $600 × 5% × 4 = $120.
6. $700 is invested at 5% simple interest per year for 6 years. How much simple interest is earned?
$210
Simple interest I = P × r × t = $700 × 5% × 6 = $210.
7. $1300 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$91
Simple interest I = P × r × t = $1300 × 7% × 1 = $91.
8. $1500 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$525
Simple interest I = P × r × t = $1500 × 7% × 5 = $525.
9. $1800 is invested at 7% simple interest per year for 3 years. How much simple interest is earned?
$378
Simple interest I = P × r × t = $1800 × 7% × 3 = $378.
10. $700 is invested at 4% simple interest per year for 6 years. How much simple interest is earned?
$168
Simple interest I = P × r × t = $700 × 4% × 6 = $168.
11. $2000 is invested at 7% simple interest per year for 5 years. How much simple interest is earned?
$700
Simple interest I = P × r × t = $2000 × 7% × 5 = $700.
12. $1400 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$98
Simple interest I = P × r × t = $1400 × 7% × 1 = $98.

12 questions · Seed 54 · Age guidance, not curriculum certification