To get the most precise estimate for the sum of $4,218 + 3,891$, which rounding method is best?

Rounding both numbers to the nearest thousand

Rounding both numbers to the nearest hundred

Rounding only the first number to the nearest thousand

Rounding only the second number to the nearest hundred

A farmer calculates that she needs 530 pounds of fertilizer. It is sold in 50-pound bags. Why must she buy 11 bags (550 pounds) instead of 10 bags (500 pounds)?

Because 530 is closer to 550 than to 500

Because standard rounding rules say to round 3 down

To ensure she has enough fertilizer for her entire field

Estimation for Sums, Differences, and Reasonableness Practice — Grade 4 math

Lesson 7: Estimation for Sums, Differences, and Reasonableness — Practice Questions

1. A charity needs 723 meals for an event. If meals are prepared in batches of 100, what is the minimum number of meals they must prepare to have enough for everyone? ___
2. The official number of runners in a city marathon was 28,745. Which number is the most appropriate estimate to use for a quick newspaper headline?
- A. 28,745
- B. 28,750
- C. 29,000
- D. 28,000
3. To get the most precise estimate for the sum of $4,218 + 3,891$, which rounding method is best?
- A. Rounding both numbers to the nearest thousand
- B. Rounding both numbers to the nearest hundred
- C. Rounding only the first number to the nearest thousand
- D. Rounding only the second number to the nearest hundred
4. A library needs to buy 845 protective book covers. If the covers are only sold in packs of 10, what is the total number of covers the library must purchase? ___
5. A farmer calculates that she needs 530 pounds of fertilizer. It is sold in 50-pound bags. Why must she buy 11 bags (550 pounds) instead of 10 bags (500 pounds)?
- A. Because 530 is closer to 550 than to 500
- B. Because standard rounding rules say to round 3 down
- C. To ensure she has enough fertilizer for her entire field
- D. To get a better price per bag
6. A city's population is 476,391. Rounded to the nearest ten thousand, the population is ___.
7. A concert hall has 4,788 seats. To ensure every person gets a program, the event manager needs to estimate how many to print. Which estimate is most appropriate?
- A. 4,000, because it's a round number.
- B. 4,700, because it's less than the actual number.
- C. 4,800, because it's better to have extra programs than not enough.
- D. 5,000, because it's too many extra.
8. A website had 382,105 views on Monday and 117,940 on Tuesday. Estimate the difference by rounding each number to the nearest ten thousand. The estimated difference is ___.
9. Consider the number 527,491. Which of the following estimates is closest to the actual number?
- A. 500,000 (rounded to the nearest hundred thousand)
- B. 530,000 (rounded to the nearest ten thousand)
- C. 527,000 (rounded to the nearest thousand)
- D. 527,500 (rounded to the nearest hundred)
10. A large library system has 653,821 books. If this number is rounded to the nearest thousand, the result is ___.