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.

New variation Try interactive challenge Browse templates

Age band:Ages 13-15 Ages 16-18

Choose “Save as PDF” to keep a copy. Use your browser’s paper setting for A4 or Letter.

Worksheet StudioPractice pack · Ages 13-15

Simple interest & savings

Take your time. Show your thinking.

1. $400 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$400 · 5% · 4 · Simple interest & savings
2. $1300 is invested at 2% simple interest per year for 4 years. How much simple interest is earned?
$1300 · 2% · 4 · Simple interest & savings
3. $500 is invested at 8% simple interest per year for 6 years. How much simple interest is earned?
$500 · 8% · 6 · Simple interest & savings
4. $100 is invested at 2% simple interest per year for 1 year. How much simple interest is earned?
$100 · 2% · 1 · Simple interest & savings
5. $1100 is invested at 2% simple interest per year for 2 years. How much simple interest is earned?
$1100 · 2% · 2 · Simple interest & savings
6. $100 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$100 · 5% · 1 · Simple interest & savings
7. $300 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$300 · 4% · 3 · Simple interest & savings
8. $600 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$600 · 7% · 1 · Simple interest & savings
9. $1400 is invested at 6% simple interest per year for 5 years. How much simple interest is earned?
$1400 · 6% · 5 · Simple interest & savings
10. $1400 is invested at 9% simple interest per year for 2 years. How much simple interest is earned?
$1400 · 9% · 2 · Simple interest & savings
11. $600 is invested at 9% simple interest per year for 6 years. How much simple interest is earned?
$600 · 9% · 6 · Simple interest & savings
12. $1900 is invested at 7% simple interest per year for 4 years. How much simple interest is earned?
$1900 · 7% · 4 · Simple interest & savings

12 questions · Seed 55 · 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. $400 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$80
Simple interest I = P × r × t = $400 × 5% × 4 = $80.
2. $1300 is invested at 2% simple interest per year for 4 years. How much simple interest is earned?
$104
Simple interest I = P × r × t = $1300 × 2% × 4 = $104.
3. $500 is invested at 8% simple interest per year for 6 years. How much simple interest is earned?
$240
Simple interest I = P × r × t = $500 × 8% × 6 = $240.
4. $100 is invested at 2% simple interest per year for 1 year. How much simple interest is earned?
$2
Simple interest I = P × r × t = $100 × 2% × 1 = $2.
5. $1100 is invested at 2% simple interest per year for 2 years. How much simple interest is earned?
$44
Simple interest I = P × r × t = $1100 × 2% × 2 = $44.
6. $100 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$5
Simple interest I = P × r × t = $100 × 5% × 1 = $5.
7. $300 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$36
Simple interest I = P × r × t = $300 × 4% × 3 = $36.
8. $600 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$42
Simple interest I = P × r × t = $600 × 7% × 1 = $42.
9. $1400 is invested at 6% simple interest per year for 5 years. How much simple interest is earned?
$420
Simple interest I = P × r × t = $1400 × 6% × 5 = $420.
10. $1400 is invested at 9% simple interest per year for 2 years. How much simple interest is earned?
$252
Simple interest I = P × r × t = $1400 × 9% × 2 = $252.
11. $600 is invested at 9% simple interest per year for 6 years. How much simple interest is earned?
$324
Simple interest I = P × r × t = $600 × 9% × 6 = $324.
12. $1900 is invested at 7% simple interest per year for 4 years. How much simple interest is earned?
$532
Simple interest I = P × r × t = $1900 × 7% × 4 = $532.

12 questions · Seed 55 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 13-15

Simple interest & savings

Take your time. Show your thinking.

1. $400 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$400 · 5% · 4 · Simple interest & savings
2. $1300 is invested at 2% simple interest per year for 4 years. How much simple interest is earned?
$1300 · 2% · 4 · Simple interest & savings
3. $500 is invested at 8% simple interest per year for 6 years. How much simple interest is earned?
$500 · 8% · 6 · Simple interest & savings
4. $100 is invested at 2% simple interest per year for 1 year. How much simple interest is earned?
$100 · 2% · 1 · Simple interest & savings
5. $1100 is invested at 2% simple interest per year for 2 years. How much simple interest is earned?
$1100 · 2% · 2 · Simple interest & savings
6. $100 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$100 · 5% · 1 · Simple interest & savings
7. $300 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$300 · 4% · 3 · Simple interest & savings
8. $600 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$600 · 7% · 1 · Simple interest & savings
9. $1400 is invested at 6% simple interest per year for 5 years. How much simple interest is earned?
$1400 · 6% · 5 · Simple interest & savings
10. $1400 is invested at 9% simple interest per year for 2 years. How much simple interest is earned?
$1400 · 9% · 2 · Simple interest & savings
11. $600 is invested at 9% simple interest per year for 6 years. How much simple interest is earned?
$600 · 9% · 6 · Simple interest & savings
12. $1900 is invested at 7% simple interest per year for 4 years. How much simple interest is earned?
$1900 · 7% · 4 · Simple interest & savings

12 questions · Seed 55 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 13-15

Simple interest & savings

Answers and reasoning. Review before teaching.

1. $400 is invested at 5% simple interest per year for 4 years. How much simple interest is earned?
$80
Simple interest I = P × r × t = $400 × 5% × 4 = $80.
2. $1300 is invested at 2% simple interest per year for 4 years. How much simple interest is earned?
$104
Simple interest I = P × r × t = $1300 × 2% × 4 = $104.
3. $500 is invested at 8% simple interest per year for 6 years. How much simple interest is earned?
$240
Simple interest I = P × r × t = $500 × 8% × 6 = $240.
4. $100 is invested at 2% simple interest per year for 1 year. How much simple interest is earned?
$2
Simple interest I = P × r × t = $100 × 2% × 1 = $2.
5. $1100 is invested at 2% simple interest per year for 2 years. How much simple interest is earned?
$44
Simple interest I = P × r × t = $1100 × 2% × 2 = $44.
6. $100 is invested at 5% simple interest per year for 1 year. How much simple interest is earned?
$5
Simple interest I = P × r × t = $100 × 5% × 1 = $5.
7. $300 is invested at 4% simple interest per year for 3 years. How much simple interest is earned?
$36
Simple interest I = P × r × t = $300 × 4% × 3 = $36.
8. $600 is invested at 7% simple interest per year for 1 year. How much simple interest is earned?
$42
Simple interest I = P × r × t = $600 × 7% × 1 = $42.
9. $1400 is invested at 6% simple interest per year for 5 years. How much simple interest is earned?
$420
Simple interest I = P × r × t = $1400 × 6% × 5 = $420.
10. $1400 is invested at 9% simple interest per year for 2 years. How much simple interest is earned?
$252
Simple interest I = P × r × t = $1400 × 9% × 2 = $252.
11. $600 is invested at 9% simple interest per year for 6 years. How much simple interest is earned?
$324
Simple interest I = P × r × t = $600 × 9% × 6 = $324.
12. $1900 is invested at 7% simple interest per year for 4 years. How much simple interest is earned?
$532
Simple interest I = P × r × t = $1900 × 7% × 4 = $532.

12 questions · Seed 55 · Age guidance, not curriculum certification