Success TutoringWorksheets

Year 11 Simple and Compound Interest Worksheet — Level 3 — Practice Set 3 — Answers

Answer sheet with worked solutions for the Year 11 financial mathematics worksheet.

Download answers PDFPrint answersBack to worksheet
Success TutoringWorksheetsAnswer sheetYear 11 · Mathematics · Financial Mathematics

Year 11 Simple and Compound Interest Worksheet — Level 3 — Practice Set 3 — Answers

Show your working. Write the rate as a decimal (5% = 0.05). Round money to the nearest cent.

1.$6,250.00 is invested at 6% per year, compounded yearly, for 2 years. Find the final amount and the interest earned, to the nearest cent.

Answer: Amount $7,022.50; interest $772.50

  1. A = P(1 + r)n = $6,250.00 × (1 + 0.06)2
  2. = $6,250.00 × 1.1236
  3. ≈ $7,022.50
  4. Interest = $7,022.50 − $6,250.00 = $772.50
2.$4,000.00 is invested at 6% per year, compounded yearly, for 10 years. Find the final amount and the interest earned, to the nearest cent.

Answer: Amount $7,163.39; interest $3,163.39

  1. A = P(1 + r)n = $4,000.00 × (1 + 0.06)10
  2. = $4,000.00 × 1.790848
  3. ≈ $7,163.39
  4. Interest = $7,163.39 − $4,000.00 = $3,163.39
3.$12,000.00 is invested at 4.5% per year, compounded yearly, for 6 years. Find the final amount and the interest earned, to the nearest cent.

Answer: Amount $15,627.12; interest $3,627.12

  1. A = P(1 + r)n = $12,000.00 × (1 + 0.045)6
  2. = $12,000.00 × 1.30226
  3. ≈ $15,627.12
  4. Interest = $15,627.12 − $12,000.00 = $3,627.12
4.Compare $11,500.00 invested for 6 years at 4.5% per year as simple interest and as interest compounded yearly. How much more does compound interest earn, to the nearest cent?

Answer: $370.99

  1. Simple: I = $11,500.00 × 0.045 × 6 = $3,105.00
  2. Compound: A = $11,500.00 × 1.0456 ≈ $14,975.99, so interest ≈ $3,475.99
  3. Difference = $3,475.99 − $3,105.00 = $370.99
5.$4,250.00 is invested at 5% per year, compounded yearly, for 3 years. Find the final amount and the interest earned, to the nearest cent.

Answer: Amount $4,919.91; interest $669.91

  1. A = P(1 + r)n = $4,250.00 × (1 + 0.05)3
  2. = $4,250.00 × 1.157625
  3. ≈ $4,919.91
  4. Interest = $4,919.91 − $4,250.00 = $669.91
6.Compare $1,250.00 invested for 9 years at 4% per year as simple interest and as interest compounded yearly. How much more does compound interest earn, to the nearest cent?

Answer: $79.14

  1. Simple: I = $1,250.00 × 0.04 × 9 = $450.00
  2. Compound: A = $1,250.00 × 1.049 ≈ $1,779.14, so interest ≈ $529.14
  3. Difference = $529.14 − $450.00 = $79.14
7.Compare $12,000.00 invested for 3 years at 6% per year as simple interest and as interest compounded yearly. How much more does compound interest earn, to the nearest cent?

Answer: $132.19

  1. Simple: I = $12,000.00 × 0.06 × 3 = $2,160.00
  2. Compound: A = $12,000.00 × 1.063 ≈ $14,292.19, so interest ≈ $2,292.19
  3. Difference = $2,292.19 − $2,160.00 = $132.19
8.$12,000.00 is invested at 4% per year, compounded yearly, for 5 years. Find the final amount and the interest earned, to the nearest cent.

Answer: Amount $14,599.83; interest $2,599.83

  1. A = P(1 + r)n = $12,000.00 × (1 + 0.04)5
  2. = $12,000.00 × 1.216653
  3. ≈ $14,599.83
  4. Interest = $14,599.83 − $12,000.00 = $2,599.83
Free worksheets at worksheets.successtutoring.com · © Success Tutoring · Free for personal and classroom use

Marking tips

  • Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
  • For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
  • Celebrate what went well first, then pick one thing to work on next.