Math Main Page => Exercises - Math III
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Goal: to practice how to make use of distributive property on special numbers, like (A + B) * (A - B) = A*A - B*B, A*C +B*C = (A + B ) *C, A*C - B*C = (A-B) * C
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Friday December 12 2025 06:55:27 PM | Friday December 12 2025 06:55:27 PMFlip Answers |
| 1) | 96 * 104 = | | 1) 100 * 100 - 4 * 4 = 9984 |
| 2) | 407 * 393 = | | 2) 400 * 400 - 7 * 7 = 159951 |
| 3) | 93 * 107 = | | 3) 100 * 100 - 7 * 7 = 9951 |
| 4) | 405 * 395 = | | 4) 400 * 400 - 5 * 5 = 159975 |
| 5) | 391 * 409 = | | 5) 400 * 400 - 9 * 9 = 159919 |
| 6) | 397 * 403 = | | 6) 400 * 400 - 3 * 3 = 159991 |
| 7) | 90 * 110 = | | 7) 100 * 100 - 10 * 10 = 9900 |
| 8) | 110 * 90 = | | 8) 100 * 100 - 10 * 10 = 9900 |
| 9) | 108 * 92 = | | 9) 100 * 100 - 8 * 8 = 9936 |
| 10) | 192 * 208 = | | 10) 200 * 200 - 8 * 8 = 39936 |
| 11) | 248 * 35 - 35 * 48 = | | 11) ( 248 - 48) * 35 = 7000 |
| 12) | 36 * 55 + 45 * 36 = | | 12) ( 55 + 45) * 36 = 3600 |
| 13) | 88 * 256 - 88 * 56 = | | 13) ( 256 - 56) * 88 = 17600 |
| 14) | 62 * 21 + 38 * 21 = | | 14) ( 38 + 62) * 21 = 2100 |
| 15) | 152 * 25 + 25 * 48 = | | 15) ( 152 + 48) * 25 = 5000 |
| 16) | 270 * 86 - 86 * 70 = | | 16) ( 270 - 70) * 86 = 17200 |
| 17) | 31 * 41 + 31 * 59 = | | 17) ( 41 + 59) * 31 = 3100 |
| 18) | 40 * 69 + 160 * 69 = | | 18) ( 160 + 40) * 69 = 13800 |
| 19) | 93 * 39 + 61 * 93 = | | 19) ( 61 + 39) * 93 = 9300 |
| 20) | 60 * 167 - 60 * 67 = | | 20) ( 167 - 67) * 60 = 6000 |
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Score: ______________ | |