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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Wednesday May 06 2026
08:02:01 PM | Wednesday May 06 2026
08:02:01 PMFlip Answers |
| 1) | 109 * 91 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 395 * 405 = | | 2) 400 * 400 - 5 * 5 = 159975 |
| 3) | 291 * 309 = | | 3) 300 * 300 - 9 * 9 = 89919 |
| 4) | 107 * 93 = | | 4) 100 * 100 - 7 * 7 = 9951 |
| 5) | 304 * 296 = | | 5) 300 * 300 - 4 * 4 = 89984 |
| 6) | 206 * 194 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 195 * 205 = | | 7) 200 * 200 - 5 * 5 = 39975 |
| 8) | 106 * 94 = | | 8) 100 * 100 - 6 * 6 = 9964 |
| 9) | 408 * 392 = | | 9) 400 * 400 - 8 * 8 = 159936 |
| 10) | 205 * 195 = | | 10) 200 * 200 - 5 * 5 = 39975 |
| 11) | 158 * 82 - 82 * 58 = | | 11) ( 158 - 58) * 82 = 8200 |
| 12) | 42 * 161 - 42 * 61 = | | 12) ( 161 - 61) * 42 = 4200 |
| 13) | 64 * 96 + 36 * 96 = | | 13) ( 36 + 64) * 96 = 9600 |
| 14) | 36 * 260 - 36 * 60 = | | 14) ( 260 - 60) * 36 = 7200 |
| 15) | 241 * 66 - 66 * 41 = | | 15) ( 241 - 41) * 66 = 13200 |
| 16) | 52 * 38 + 162 * 52 = | | 16) ( 162 + 38) * 52 = 10400 |
| 17) | 87 * 137 + 63 * 87 = | | 17) ( 137 + 63) * 87 = 17400 |
| 18) | 40 * 67 + 67 * 160 = | | 18) ( 160 + 40) * 67 = 13400 |
| 19) | 159 * 38 - 59 * 38 = | | 19) ( 159 - 59) * 38 = 3800 |
| 20) | 256 * 25 - 56 * 25 = | | 20) ( 256 - 56) * 25 = 5000 |
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Score: ______________ | |
