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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Saturday June 06 2026
05:36:09 PM | Saturday June 06 2026
05:36:09 PMFlip Answers |
| 1) | 392 * 408 = | | 1) 400 * 400 - 8 * 8 = 159936 |
| 2) | 193 * 207 = | | 2) 200 * 200 - 7 * 7 = 39951 |
| 3) | 109 * 91 = | | 3) 100 * 100 - 9 * 9 = 9919 |
| 4) | 310 * 290 = | | 4) 300 * 300 - 10 * 10 = 89900 |
| 5) | 199 * 201 = | | 5) 200 * 200 - 1 * 1 = 39999 |
| 6) | 293 * 307 = | | 6) 300 * 300 - 7 * 7 = 89951 |
| 7) | 395 * 405 = | | 7) 400 * 400 - 5 * 5 = 159975 |
| 8) | 94 * 106 = | | 8) 100 * 100 - 6 * 6 = 9964 |
| 9) | 196 * 204 = | | 9) 200 * 200 - 4 * 4 = 39984 |
| 10) | 199 * 201 = | | 10) 200 * 200 - 1 * 1 = 39999 |
| 11) | 28 * 236 - 36 * 28 = | | 11) ( 236 - 36) * 28 = 5600 |
| 12) | 59 * 53 + 59 * 47 = | | 12) ( 47 + 53) * 59 = 5900 |
| 13) | 71 * 168 - 71 * 68 = | | 13) ( 168 - 68) * 71 = 7100 |
| 14) | 127 * 61 + 61 * 73 = | | 14) ( 127 + 73) * 61 = 12200 |
| 15) | 143 * 66 + 57 * 66 = | | 15) ( 143 + 57) * 66 = 13200 |
| 16) | 51 * 143 - 43 * 51 = | | 16) ( 143 - 43) * 51 = 5100 |
| 17) | 238 * 57 - 38 * 57 = | | 17) ( 238 - 38) * 57 = 11400 |
| 18) | 93 * 43 + 57 * 93 = | | 18) ( 43 + 57) * 93 = 9300 |
| 19) | 35 * 80 + 80 * 65 = | | 19) ( 65 + 35) * 80 = 8000 |
| 20) | 163 * 26 - 26 * 63 = | | 20) ( 163 - 63) * 26 = 2600 |
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Score: ______________ | |
