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 January 23 2026
06:10:46 PM | Friday January 23 2026
06:10:46 PMFlip Answers |
| 1) | 109 * 91 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 306 * 294 = | | 2) 300 * 300 - 6 * 6 = 89964 |
| 3) | 106 * 94 = | | 3) 100 * 100 - 6 * 6 = 9964 |
| 4) | 410 * 390 = | | 4) 400 * 400 - 10 * 10 = 159900 |
| 5) | 197 * 203 = | | 5) 200 * 200 - 3 * 3 = 39991 |
| 6) | 206 * 194 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 90 * 110 = | | 7) 100 * 100 - 10 * 10 = 9900 |
| 8) | 207 * 193 = | | 8) 200 * 200 - 7 * 7 = 39951 |
| 9) | 207 * 193 = | | 9) 200 * 200 - 7 * 7 = 39951 |
| 10) | 107 * 93 = | | 10) 100 * 100 - 7 * 7 = 9951 |
| 11) | 64 * 260 - 60 * 64 = | | 11) ( 260 - 60) * 64 = 12800 |
| 12) | 272 * 36 - 36 * 72 = | | 12) ( 272 - 72) * 36 = 7200 |
| 13) | 73 * 92 + 27 * 92 = | | 13) ( 27 + 73) * 92 = 9200 |
| 14) | 147 * 43 - 43 * 47 = | | 14) ( 147 - 47) * 43 = 4300 |
| 15) | 64 * 142 - 64 * 42 = | | 15) ( 142 - 42) * 64 = 6400 |
| 16) | 171 * 92 - 92 * 71 = | | 16) ( 171 - 71) * 92 = 9200 |
| 17) | 57 * 161 - 57 * 61 = | | 17) ( 161 - 61) * 57 = 5700 |
| 18) | 130 * 95 + 95 * 70 = | | 18) ( 130 + 70) * 95 = 19000 |
| 19) | 35 * 57 + 43 * 35 = | | 19) ( 43 + 57) * 35 = 3500 |
| 20) | 62 * 38 + 38 * 38 = | | 20) ( 62 + 38) * 38 = 3800 |
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Score: ______________ | |
