3rd Grade Rounding to the Nearest 10 and 100 Test Solutions and Scoring (PDF)
This grade 3 rounding test answers for 3rd Grade covers rounding to the nearest 10 and 100 (Common Core 3.NBT.A.1), with a free PDF to print.
Grade 3 · Common Core State Standards: 3.NBT.A.1
Grade 3 rounding test answers: worked solutions
Question 1 – Nearest ten [2 pts]
- The ones digit 8 rounds up: 60.
- The ones digit 3 rounds down: 140.
Scoring: 1 point for each correct number.
Question 2 – Nearest hundred [2 pts]
- 672 is past the halfway point 650: 700.
- 450 is halfway and rounds up: 500.
Scoring: 1 point for each correct number.
Question 3 – Three numbers [2 pts]
\(238\) rounds to 200. \(905\) rounds to 900. \(951\) rounds to 1,000.
Scoring: 1 point for two correct answers. 1 point for all three correct.
Question 4 – Ten and hundred [2 pts]
- The ones digit 6 rounds up: 790.
- The tens digit 8 rounds up: 800.
Scoring: 1 point for each correct number.
Question 5 – Numbers in a range [3 pts]
- 45.
- 54.
- No. 55 is halfway between 50 and 60, so it rounds up to 60.
Scoring: 1 point for each part.
Question 6 – Library estimate [3 pts]
- \(400 + 300 = 700\).
- \(390 + 260 = 650\).
- \(387 + 256 = 643\). The estimate 650 is closer: it is 7 away, while 700 is 57 away.
Scoring: 1 point for each part.
Question 7 – Find the mistake [2 pts]
A ones digit of 5 rounds up. So 465 is rounded up to 470.
Scoring: 1 point for the explanation. 1 point for 470.
Question 8 – Event crowd [2 pts]
The least is 750 and the greatest is 849.
Scoring: 1 point for each number.
Question 9 – Estimate a difference [2 pts]
Estimate: \(900 – 500 = 400\). Exact: \(912 – 487 = 425\).
Scoring: 1 point for the estimate. 1 point for the exact difference.
Total score
20 points
Key facts behind this grade 3 rounding test answers
- Rounding to the nearest 10 depends on the ones digit.
- Rounding to the nearest 100 depends on the tens digit.
- A digit of 5 or more rounds up. A digit of 4 or less rounds down.
- A number exactly halfway rounds up, so 45 rounds to 50.
- Rounded numbers make quick estimates for sums and differences.
How to use this grade 3 rounding test answers
Score your test with the point values shown for each question. Then read the worked solution of every question where you lost points and note the method to review.
All Grade 3 chapters: Grade 3 math.
