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Calculate simple interest and the cost of borrowing · Grade 9 · F1.3

Name: ______________________

Date: ______________________

1
Priya invests $900 at a simple interest rate of 3% per year for 1 years. How much interest does she earn?
Warm-up
Answer:
2
Priya invests $600 at a simple interest rate of 6% per year for 4 years. How much interest does she earn?
Warm-up
Answer:
3
Priya invests $1100 at a simple interest rate of 1% per year for 3 years. How much interest does she earn?
Warm-up
Answer:
4
Priya invests $2000 at a simple interest rate of 7% per year for 5 years. How much will she have in total?
On level
Answer:
5
Priya invests $1500 at a simple interest rate of 7% per year for 2 years. How much will she have in total?
On level
Answer:
6
Priya invests $800 at a simple interest rate of 6% per year for 2 years. How much will she have in total?
On level
Answer:
7
A car loan of $6500 is charged simple interest at 11% per year and repaid after 4 years. What is the total amount to repay?
Challenge
Answer:
8
A car loan of $3000 is charged simple interest at 10% per year and repaid after 2 years. What is the total amount to repay?
Challenge
Answer:
9
A car loan of $10000 is charged simple interest at 4% per year and repaid after 5 years. What is the total amount to repay?
Challenge
Answer:

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Worksheet code: eyJzIjoiZmluYW5jaWFsLXNpbXBsZS1pbnRlcmVzdCIsImQiOlsxMDE1MTY4MywyMDExNzUyNTc5LDEzODAxMDA5MzcsMjA0OTkyNzg3MCw1NDY4MTg4MzMsMjA2NjA1ODgxOCwxNzc1NjczNDQzLDI3MTA1ODk0OSw3MjgxNDMwMTJdLCJ2IjoxfQ.6631fccca1e7

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Answer key · Calculate simple interest and the cost of borrowing

1.
27 — I = P × r × t = $900 × 3% × 1 = $27.
2.
144 — I = P × r × t = $600 × 6% × 4 = $144.
3.
33 — I = P × r × t = $1100 × 1% × 3 = $33.
4.
2700 — Interest = $700; total = $2000 + $700 = $2700.
5.
1710 — Interest = $210; total = $1500 + $210 = $1710.
6.
896 — Interest = $96; total = $800 + $96 = $896.
7.
9360 — Interest = $6500 × 11% × 4 = $2860; total to repay = $6500 + $2860 = $9360.
8.
3600 — Interest = $3000 × 10% × 2 = $600; total to repay = $3000 + $600 = $3600.
9.
12000 — Interest = $10000 × 4% × 5 = $2000; total to repay = $10000 + $2000 = $12000.