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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Monday December 08 2025
09:45:44 PM | Monday December 08 2025
09:45:44 PMFlip Answers |
| 1) | 396 * 404 = | | 1) 400 * 400 - 4 * 4 = 159984 |
| 2) | 395 * 405 = | | 2) 400 * 400 - 5 * 5 = 159975 |
| 3) | 206 * 194 = | | 3) 200 * 200 - 6 * 6 = 39964 |
| 4) | 192 * 208 = | | 4) 200 * 200 - 8 * 8 = 39936 |
| 5) | 93 * 107 = | | 5) 100 * 100 - 7 * 7 = 9951 |
| 6) | 204 * 196 = | | 6) 200 * 200 - 4 * 4 = 39984 |
| 7) | 195 * 205 = | | 7) 200 * 200 - 5 * 5 = 39975 |
| 8) | 396 * 404 = | | 8) 400 * 400 - 4 * 4 = 159984 |
| 9) | 298 * 302 = | | 9) 300 * 300 - 2 * 2 = 89996 |
| 10) | 91 * 109 = | | 10) 100 * 100 - 9 * 9 = 9919 |
| 11) | 23 * 64 + 36 * 23 = | | 11) ( 64 + 36) * 23 = 2300 |
| 12) | 175 * 21 - 21 * 75 = | | 12) ( 175 - 75) * 21 = 2100 |
| 13) | 54 * 22 + 22 * 146 = | | 13) ( 146 + 54) * 22 = 4400 |
| 14) | 33 * 69 + 67 * 69 = | | 14) ( 33 + 67) * 69 = 6900 |
| 15) | 51 * 33 + 33 * 49 = | | 15) ( 49 + 51) * 33 = 3300 |
| 16) | 237 * 94 - 94 * 37 = | | 16) ( 237 - 37) * 94 = 18800 |
| 17) | 134 * 58 + 66 * 58 = | | 17) ( 134 + 66) * 58 = 11600 |
| 18) | 77 * 166 - 77 * 66 = | | 18) ( 166 - 66) * 77 = 7700 |
| 19) | 46 * 143 - 46 * 43 = | | 19) ( 143 - 43) * 46 = 4600 |
| 20) | 145 * 39 - 45 * 39 = | | 20) ( 145 - 45) * 39 = 3900 |
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Score: ______________ | |
