Let’s solve each problem step by step.
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Step 1: Estimate by rounding to the nearest thousand.
We’ll round each number to the nearest thousand, then add or subtract.
Problem 1:
4,575 → rounds to
5,000
1,836 → rounds to
2,000
5,000 – 2,000 =
3,000
✔ Answer:
3,000
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Problem 2:
7,150 → rounds to
7,000
6,416 → rounds to
6,000
7,000 + 6,000 =
13,000
✔ Answer:
13,000
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Problem 3:
12,739 → rounds to
13,000
5,895 → rounds to
6,000
13,000 – 6,000 =
7,000
✔ Answer:
7,000
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Problem 4:
21,239 → rounds to
21,000
14,710 → rounds to
15,000
21,000 – 15,000 =
6,000
✔ Answer:
6,000
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Problem 5:
39,758 → rounds to
40,000
21,837 → rounds to
22,000
40,000 + 22,000 =
62,000
✔ Answer:
62,000
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Problem 6:
145,795 → rounds to
146,000
86,439 → rounds to
86,000
146,000 + 86,000 =
232,000
✔ Answer:
232,000
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Step 2: Estimate by rounding to the nearest ten thousand.
Now we round to the nearest ten thousand (look at the thousands digit — if it’s 5 or more, round up; less than 5, round down).
Problem 7:
43,286 → rounds to
40,000
11,723 → rounds to
10,000
40,000 + 10,000 =
50,000
✔ Answer:
50,000
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Problem 8:
29,841 → rounds to
30,000
16,372 → rounds to
20,000
30,000 – 20,000 =
10,000
✔ Answer:
10,000
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Problem 9:
74,185 → rounds to
70,000
16,347 → rounds to
20,000
70,000 + 20,000 =
90,000
✔ Answer:
90,000
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Problem 10:
139,216 → rounds to
140,000
83,950 → rounds to
80,000
140,000 – 80,000 =
60,000
✔ Answer:
60,000
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Problem 11:
437,615 → rounds to
440,000
168,212 → rounds to
170,000
440,000 – 170,000 =
270,000
✔ Answer:
270,000
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Problem 12:
512,817 → rounds to
510,000
273,548 → rounds to
270,000
510,000 + 270,000 =
780,000
✔ Answer:
780,000
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Final Answer:
1. 3,000
2. 13,000
3. 7,000
4. 6,000
5. 62,000
6. 232,000
7. 50,000
8. 10,000
9. 90,000
10. 60,000
11. 270,000
12. 780,000
Parent Tip: Review the logic above to help your child master the concept of addition rounding worksheet.
