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 February 20 2026
08:42:23 AM | Friday February 20 2026
08:42:23 AMFlip Answers |
| 1) | 91 * 109 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 199 * 201 = | | 2) 200 * 200 - 1 * 1 = 39999 |
| 3) | 407 * 393 = | | 3) 400 * 400 - 7 * 7 = 159951 |
| 4) | 407 * 393 = | | 4) 400 * 400 - 7 * 7 = 159951 |
| 5) | 403 * 397 = | | 5) 400 * 400 - 3 * 3 = 159991 |
| 6) | 402 * 398 = | | 6) 400 * 400 - 2 * 2 = 159996 |
| 7) | 204 * 196 = | | 7) 200 * 200 - 4 * 4 = 39984 |
| 8) | 403 * 397 = | | 8) 400 * 400 - 3 * 3 = 159991 |
| 9) | 109 * 91 = | | 9) 100 * 100 - 9 * 9 = 9919 |
| 10) | 307 * 293 = | | 10) 300 * 300 - 7 * 7 = 89951 |
| 11) | 91 * 267 - 91 * 67 = | | 11) ( 267 - 67) * 91 = 18200 |
| 12) | 268 * 80 - 80 * 68 = | | 12) ( 268 - 68) * 80 = 16000 |
| 13) | 97 * 73 + 97 * 127 = | | 13) ( 127 + 73) * 97 = 19400 |
| 14) | 154 * 46 - 54 * 46 = | | 14) ( 154 - 54) * 46 = 4600 |
| 15) | 138 * 46 - 46 * 38 = | | 15) ( 138 - 38) * 46 = 4600 |
| 16) | 161 * 92 - 61 * 92 = | | 16) ( 161 - 61) * 92 = 9200 |
| 17) | 81 * 157 - 81 * 57 = | | 17) ( 157 - 57) * 81 = 8100 |
| 18) | 84 * 54 + 84 * 46 = | | 18) ( 54 + 46) * 84 = 8400 |
| 19) | 153 * 88 + 88 * 47 = | | 19) ( 153 + 47) * 88 = 17600 |
| 20) | 67 * 42 + 42 * 33 = | | 20) ( 33 + 67) * 42 = 4200 |
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Score: ______________ | |
