Chapter review

Attempt independently, then review the full reasoning in the answer key.

Attempt independently, then review the full reasoning in the answer key. No name, account, or answer is transmitted to any server.

Assessment · 28 questions

Problems

The complete solutions are available here after each question and on the printable answer-key page.

A1
Subtract 1,792 − 558; show any place-value exchange.
Show answer and reasoning
Answer: 1234
Exchange a larger unit into 10 smaller units when needed. Preserve the total and subtract. Difference = 1,234; add 558 to check.
A2
Calculate 4,005 − 400; explain how you cross the zero places.
Show answer and reasoning
Answer: 3605
Rename a nonzero higher-place unit to supply ten of the next smaller units; continue exchanging across zeros. 4,005 − 400 = 3,605.
A3
Estimate 6,274 + 1,222 by rounding BOTH numbers to the nearest 100.
Show answer and reasoning
Answer: 7,500
Round 6,274 to 6,300 and 1,222 to 1,200. Estimate 6,300 + 1,200 = 7,500; it need not equal the exact answer.
A4
A museum had 3,364 tickets and sold 395. How many tickets remain?
Show answer and reasoning
Answer: 2969
Identify the whole and its parts, then compute 3,364 − 395 = 2,969. Estimate to hundreds to check size.
A5
Estimate 6,936 + 1,604 by rounding BOTH numbers to the nearest 100.
Show answer and reasoning
Answer: 8,500
Round 6,936 to 6,900 and 1,604 to 1,600. Estimate 6,900 + 1,600 = 8,500; it need not equal the exact answer.
A6
Calculate 2,020 − 546; explain how you cross the zero places.
Show answer and reasoning
Answer: 1474
Rename a nonzero higher-place unit to supply ten of the next smaller units; continue exchanging across zeros. 2,020 − 546 = 1,474.
A7
Why does 679+154 require exchanges in both ones and tens?
Show answer and reasoning
Answer: Both sums reach at least 10 units
9+4=13 ones carries 1 ten; 7+5+1=13 tens carries 1 hundred.
A8
Estimate 3,066 − 534 by rounding BOTH numbers to the nearest 100.
Show answer and reasoning
Answer: 2,600
Round 3,066 to 3,100 and 534 to 500. Estimate 3,100 − 500 = 2,600; it need not equal the exact answer.
A9
Subtract 2,112 − 698; show any place-value exchange.
Show answer and reasoning
Answer: 1414
Exchange a larger unit into 10 smaller units when needed. Preserve the total and subtract. Difference = 1,414; add 698 to check.
A10
A delivery service starts with 2,640 parcels and delivers 987. Estimate to hundreds, then compute exactly.
Show answer and reasoning
Answer: About 1,600; exactly 1,653
2,600−1,000≈1,600; 2,640−987=1,653.
A11
Subtract 1,952 − 628; show any place-value exchange.
Show answer and reasoning
Answer: 1324
Exchange a larger unit into 10 smaller units when needed. Preserve the total and subtract. Difference = 1,324; add 628 to check.
A12
Calculate 1,000 − 473; explain how you cross the zero places.
Show answer and reasoning
Answer: 527
Rename a nonzero higher-place unit to supply ten of the next smaller units; continue exchanging across zeros. 1,000 − 473 = 527.
A13
Add 568 and 847. Explain one exchange of ten units.
Show answer and reasoning
Answer: 1415
Combine ones, tens, hundreds, and thousands. Exchange 10 units for 1 in the next column whenever needed; 568 + 847 = 1,415.
A14
Find 3,000−476. Describe the exchange chain, not only the result.
Show answer and reasoning
Answer: 2,524
Regroup thousands through hundreds and tens to obtain sufficient ones. 3,000−476=2,524.
A15
Subtract 1,642 − 498; show any place-value exchange.
Show answer and reasoning
Answer: 1144
Exchange a larger unit into 10 smaller units when needed. Preserve the total and subtract. Difference = 1,144; add 498 to check.
A16
Estimate 2,735 − 343 by rounding BOTH numbers to the nearest 10.
Show answer and reasoning
Answer: 2,400
Round 2,735 to 2,740 and 343 to 340. Estimate 2,740 − 340 = 2,400; it need not equal the exact answer.
A17
Calculate 3,040 − 327; explain how you cross the zero places.
Show answer and reasoning
Answer: 2713
Rename a nonzero higher-place unit to supply ten of the next smaller units; continue exchanging across zeros. 3,040 − 327 = 2,713.
A18
An exhibit recorded 3,587 visitors in the morning and 466 more in the afternoon. How many altogether?
Show answer and reasoning
Answer: 4053
Identify the whole and its parts, then compute 3,587 + 466 = 4,053. Estimate to hundreds to check size.
A19
Estimate 2,073 − 1,661 by rounding BOTH numbers to the nearest 10.
Show answer and reasoning
Answer: 410
Round 2,073 to 2,070 and 1,661 to 1,660. Estimate 2,070 − 1,660 = 410; it need not equal the exact answer.
A20
A corrected difference should be 403. The smaller number is 1,978. Find the larger number.
Show answer and reasoning
Answer: 2,381
A difference of 403 means the larger is 1,978+403=2,381.
A21
Estimate 6,605 + 1,413 by rounding BOTH numbers to the nearest 10.
Show answer and reasoning
Answer: 8,020
Round 6,605 to 6,610 and 1,413 to 1,410. Estimate 6,610 + 1,410 = 8,020; it need not equal the exact answer.
A22
Estimate 5,943 + 1,031 by rounding BOTH numbers to the nearest 10.
Show answer and reasoning
Answer: 6,970
Round 5,943 to 5,940 and 1,031 to 1,030. Estimate 5,940 + 1,030 = 6,970; it need not equal the exact answer.
A23
Add 398 and 717. Explain one exchange of ten units.
Show answer and reasoning
Answer: 1115
Combine ones, tens, hundreds, and thousands. Exchange 10 units for 1 in the next column whenever needed; 398 + 717 = 1,115.
A24
Add 908 and 1,127. Explain one exchange of ten units.
Show answer and reasoning
Answer: 2035
Combine ones, tens, hundreds, and thousands. Exchange 10 units for 1 in the next column whenever needed; 908 + 1,127 = 2,035.
A25
Estimate 2,404 − 1,852 by rounding BOTH numbers to the nearest 100.
Show answer and reasoning
Answer: 500
Round 2,404 to 2,400 and 1,852 to 1,900. Estimate 2,400 − 1,900 = 500; it need not equal the exact answer.
A26
A museum had 3,810 tickets and sold 537. How many tickets remain?
Show answer and reasoning
Answer: 3273
Identify the whole and its parts, then compute 3,810 − 537 = 3,273. Estimate to hundreds to check size.
A27
Add 738 and 987. Explain one exchange of ten units.
Show answer and reasoning
Answer: 1725
Combine ones, tens, hundreds, and thousands. Exchange 10 units for 1 in the next column whenever needed; 738 + 987 = 1,725.
A28
An exhibit recorded 4,033 visitors in the morning and 608 more in the afternoon. How many altogether?
Show answer and reasoning
Answer: 4641
Identify the whole and its parts, then compute 4,033 + 608 = 4,641. Estimate to hundreds to check size.

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