Practice A: Addition and Subtraction
Chapter 2 · Consolidation 1
Mixed consolidation. Attempt problems independently before revealing the solutions.
Calculate 474,869 + 110,333.
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Align the place values; add ones, tens, hundreds and higher units, exchanging 10 of one unit for 1 of the next when needed.
Calculate 635,468 − 1,190.
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Subtract like place values, exchanging one higher unit for ten lower units when necessary. Check: 634,278 + 1,190 = 635,468.
Use compensation to add 410,958 and 95,813. What is the exact sum?
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Increase 410,958 by 42 to a friendly multiple of 1,000, then subtract 42 from the sum to preserve the total.
Calculate 460,622 − 188,573 by adding 50 to both quantities first. What answer do you get?
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Equal adjustment preserves the difference: (460,672) − (188,623) = 272,049.
A library had 83,407 books, received 151,453 more, then lent 75,726. How many books are there now?
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First add 234,860. Then subtract 75,726 to obtain 159,134.
Calculate 36,424 + 39,208.
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Align the place values; add ones, tens, hundreds and higher units, exchanging 10 of one unit for 1 of the next when needed.
Calculate 262,637 − 11,288.
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Subtract like place values, exchanging one higher unit for ten lower units when necessary. Check: 251,349 + 11,288 = 262,637.
Use compensation to add 167,544 and 63,239. What is the exact sum?
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Increase 167,544 by 6 to a friendly multiple of 10, then subtract 6 from the sum to preserve the total.
Calculate 108,318 − 39,404 by adding 50 to both quantities first. What answer do you get?
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Equal adjustment preserves the difference: (108,368) − (39,454) = 68,914.
A library had 365,453 books, received 112,956 more, then lent 56,478. How many books are there now?
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First add 478,409. Then subtract 56,478 to obtain 421,931.
Calculate 320,324 + 23,471.
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Align the place values; add ones, tens, hundreds and higher units, exchanging 10 of one unit for 1 of the next when needed.
Calculate 441,071 − 68,953.
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Subtract like place values, exchanging one higher unit for ten lower units when necessary. Check: 372,118 + 68,953 = 441,071.
Use compensation to add 436,545 and 65,198. What is the exact sum?
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Increase 436,545 by 5 to a friendly multiple of 10, then subtract 5 from the sum to preserve the total.
Calculate 514,739 − 8,376 by adding 50 to both quantities first. What answer do you get?
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Equal adjustment preserves the difference: (514,789) − (8,426) = 506,363.
Alex and Bea have 537,378 points together. Bea has 5,348 more than Alex. How many does Alex have?
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Remove the extra 5,348 from the whole and split the rest into two equal parts: (537,378 − 5,348) ÷ 2 = 266,015.
Calculate 369,143 + 199,690.
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Align the place values; add ones, tens, hundreds and higher units, exchanging 10 of one unit for 1 of the next when needed.
Calculate 753,307 − 164,453.
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Subtract like place values, exchanging one higher unit for ten lower units when necessary. Check: 588,854 + 164,453 = 753,307.
Use compensation to add 174,505 and 163,875. What is the exact sum?
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Increase 174,505 by 495 to a friendly multiple of 1,000, then subtract 495 from the sum to preserve the total.