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 19 2025
04:29:34 PM | Friday December 19 2025
04:29:34 PMFlip Answers |
| 1) | 394 * 406 = | | 1) 400 * 400 - 6 * 6 = 159964 |
| 2) | 110 * 90 = | | 2) 100 * 100 - 10 * 10 = 9900 |
| 3) | 292 * 308 = | | 3) 300 * 300 - 8 * 8 = 89936 |
| 4) | 109 * 91 = | | 4) 100 * 100 - 9 * 9 = 9919 |
| 5) | 307 * 293 = | | 5) 300 * 300 - 7 * 7 = 89951 |
| 6) | 398 * 402 = | | 6) 400 * 400 - 2 * 2 = 159996 |
| 7) | 192 * 208 = | | 7) 200 * 200 - 8 * 8 = 39936 |
| 8) | 410 * 390 = | | 8) 400 * 400 - 10 * 10 = 159900 |
| 9) | 195 * 205 = | | 9) 200 * 200 - 5 * 5 = 39975 |
| 10) | 104 * 96 = | | 10) 100 * 100 - 4 * 4 = 9984 |
| 11) | 64 * 94 + 94 * 136 = | | 11) ( 136 + 64) * 94 = 18800 |
| 12) | 74 * 59 + 126 * 59 = | | 12) ( 126 + 74) * 59 = 11800 |
| 13) | 55 * 69 + 69 * 145 = | | 13) ( 145 + 55) * 69 = 13800 |
| 14) | 148 * 49 - 48 * 49 = | | 14) ( 148 - 48) * 49 = 4900 |
| 15) | 21 * 245 - 21 * 45 = | | 15) ( 245 - 45) * 21 = 4200 |
| 16) | 95 * 26 + 95 * 74 = | | 16) ( 26 + 74) * 95 = 9500 |
| 17) | 75 * 58 + 58 * 125 = | | 17) ( 125 + 75) * 58 = 11600 |
| 18) | 52 * 37 + 63 * 52 = | | 18) ( 37 + 63) * 52 = 5200 |
| 19) | 50 * 47 + 153 * 50 = | | 19) ( 153 + 47) * 50 = 10000 |
| 20) | 94 * 57 + 94 * 143 = | | 20) ( 143 + 57) * 94 = 18800 |
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Score: ______________ | |
