This 8.3 independent practice page 221 answer key covers questions 7 through 28 on the Go Math lesson about solving percent problems. The solutions below were calculated independently from the matching student page; they are not an official HMH teacher answer key.
Check your edition before using the answers
A sixth-grade classroom homework page identifies Go Math Lesson 8.3 independent practice on page 221. The matching publicly displayed student-page reproduction contains percent calculations and word problems. It begins question 7 with 64% of 75.
If your page starts differently, the numbering below may not apply. Page numbers can change between editions. Compare the actual exercise before transferring an answer.
8.3 independent practice page 221 answer key
Use this table to check completed work. The unit is part of the answer: a percentage, a number of objects and an amount of money are not interchangeable.
| Question | Answer |
|---|---|
| 7 | 48 tiles |
| 8 | 14 plants |
| 9 | 8 pages |
| 10 | 34 emails |
| 11 | 252 friends |
| 12 | 11 files |
| 13 | 20% |
| 14 | 8% |
| 15 | 70% |
| 16 | 75% |
| 17 | 1,400 days |
| 18 | 300 minutes |
| 19 | 40 games |
| 20 | 1,500 kilometers |
| 21 | 20 peaches |
| 22 | 300 stores |
| 23 | 9 puppies |
| 24 | 12% |
| 25 | $500 before tax |
| 26 | $48 still needed |
| 27 | $30 before tax |
| 28 | School 6 hours; eating 2.4; sleep 9.6; homework 2.4; free time 3.6 |
The three calculations behind the page
First decide whether the missing value is the part, the whole or the percentage. OpenStax explains percent as a rate per hundred. For multiplication, convert the rate into a decimal: 18% becomes 0.18, not 18.
To find a part, multiply the whole by the decimal rate. In an original practice example, 18% of 250 is 0.18 × 250 = 45. Check the size: a rate below 100% should produce less than the whole when the quantity is positive.
To find a percentage, divide the part by the whole and multiply by 100. For example, 18 out of 60 is 18 ÷ 60 × 100 = 30%. Writing only 0.3 without converting it leaves a decimal ratio rather than the requested percentage.
To find a whole, divide the part by the decimal rate. If 18 represents 30% of a group, the total is 18 ÷ 0.30 = 60. The OpenStax percent-equation method uses the same relationship: amount equals rate times base.
How to check the word problems
When tax is given, distinguish the original price from the final bill. Divide the tax amount by its decimal rate to recover the original price. Add the tax only if the question asks for the price including tax.
For a savings problem, the amount already saved is not the amount still needed. Calculate the saved portion, then subtract it from the target. Alternatively, subtract the saved percentage from 100% and calculate that remaining share.
For a full-day circle graph, multiply each decimal percentage by 24 hours. Decimal hours are not clock minutes: 0.4 hour equals 24 minutes. The five answers should add to 24 hours, providing an independent check on the arithmetic.
Frequently asked questions
Is this HMH’s official answer key?
No. These are independent solutions to the identified student exercises, with the source and edition limitation stated above.
Should I show working?
Yes. Write the relationship, substitute the quantities, calculate and include units. Follow any additional directions your teacher provides.
Why can finding the whole give a larger number?
The known amount may represent only a small share. Dividing it by a decimal below one recovers the larger total.
Are the exercises after question 28 included?
No. This answer table stops at the end of the matched page 221.
Sources
The classroom page supports lesson identification, the student-page reproduction supports exercise matching, and the two OpenStax sections explain the mathematical methods. No publisher endorsement is implied.
Related reading on using calculations for a savings goal: Sinking Fund for Car Repairs on SeesanTV.org | How Much to Save and How to Build One.
