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Grade 9 exponential growth and decay worksheets
HSF-LE.A.2 Word problems
Printable exponential growth and decay worksheets for grade 9, aligned to Common Core standard HSF-LE.A.2. Repeated doubling or halving.
Make a worksheet on this skillFree, instant, no signup. Choose 5–40 problems, three difficulty levels, and a printable answer key.
Sample problems
- A sample of 1,040 grams halves every day. How much is left after 4 days? 65 grams
- A colony of 80 bacteria grows 3 times bigger every hour. How many are there after 4 hours? 6,480
- A colony of 50 bacteria doubles every hour. How many are there after 3 hours? 400
- A sample of 90 grams shrinks to 1/3 of its size every day. How much is left after 2 days? 10 grams
- A colony of 170 bacteria doubles every hour. How many are there after 2 hours? 680
- A colony of 100 bacteria doubles every hour. How many are there after 4 hours? 1,600
- A colony of 180 bacteria grows 3 times bigger every hour. How many are there after 4 hours? 14,580
- A colony of 30 bacteria grows 3 times bigger every hour. How many are there after 4 hours? 2,430
These eight are one sample at medium difficulty — the generator makes a different set every time.
A worked example
A sample of 1,040 grams halves every day. How much is left after 4 days? 65 grams
- Divide by 2 once for each day: 2^4 = 16
- 1,040 ÷ 16 = 65 grams
Every problem on the answer key can show its steps like this — turn on “Show steps” before downloading.
About these worksheets
The wording stays familiar while the numbers change, which is what makes the method stick rather than the answer. Every sheet is generated fresh, so you can print a new one on the same skill as often as you need — different numbers, same difficulty.
Pick how many problems you want and whether they should be easy, medium or hard, then download a PDF with a matching answer key. The key can show the worked steps for every problem, which is what a parent needs to see where a wrong answer went wrong.
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