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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Thursday May 07 2026
09:35:01 PM | Thursday May 07 2026
09:35:01 PMFlip Answers |
| 1) | 110 * 90 = | | 1) 100 * 100 - 10 * 10 = 9900 |
| 2) | 95 * 105 = | | 2) 100 * 100 - 5 * 5 = 9975 |
| 3) | 292 * 308 = | | 3) 300 * 300 - 8 * 8 = 89936 |
| 4) | 99 * 101 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 404 * 396 = | | 5) 400 * 400 - 4 * 4 = 159984 |
| 6) | 99 * 101 = | | 6) 100 * 100 - 1 * 1 = 9999 |
| 7) | 201 * 199 = | | 7) 200 * 200 - 1 * 1 = 39999 |
| 8) | 207 * 193 = | | 8) 200 * 200 - 7 * 7 = 39951 |
| 9) | 92 * 108 = | | 9) 100 * 100 - 8 * 8 = 9936 |
| 10) | 96 * 104 = | | 10) 100 * 100 - 4 * 4 = 9984 |
| 11) | 68 * 248 - 68 * 48 = | | 11) ( 248 - 48) * 68 = 13600 |
| 12) | 45 * 173 - 73 * 45 = | | 12) ( 173 - 73) * 45 = 4500 |
| 13) | 85 * 29 + 71 * 85 = | | 13) ( 29 + 71) * 85 = 8500 |
| 14) | 270 * 66 - 66 * 70 = | | 14) ( 270 - 70) * 66 = 13200 |
| 15) | 49 * 161 + 39 * 49 = | | 15) ( 161 + 39) * 49 = 9800 |
| 16) | 150 * 63 - 50 * 63 = | | 16) ( 150 - 50) * 63 = 6300 |
| 17) | 130 * 55 + 55 * 70 = | | 17) ( 130 + 70) * 55 = 11000 |
| 18) | 85 * 166 - 85 * 66 = | | 18) ( 166 - 66) * 85 = 8500 |
| 19) | 69 * 70 + 131 * 70 = | | 19) ( 131 + 69) * 70 = 14000 |
| 20) | 95 * 140 - 95 * 40 = | | 20) ( 140 - 40) * 95 = 9500 |
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Score: ______________ | |
