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 October 02 2026
08:44:08 AM | Friday October 02 2026
08:44:08 AMFlip Answers |
| 1) | 91 * 109 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 207 * 193 = | | 2) 200 * 200 - 7 * 7 = 39951 |
| 3) | 403 * 397 = | | 3) 400 * 400 - 3 * 3 = 159991 |
| 4) | 105 * 95 = | | 4) 100 * 100 - 5 * 5 = 9975 |
| 5) | 209 * 191 = | | 5) 200 * 200 - 9 * 9 = 39919 |
| 6) | 199 * 201 = | | 6) 200 * 200 - 1 * 1 = 39999 |
| 7) | 403 * 397 = | | 7) 400 * 400 - 3 * 3 = 159991 |
| 8) | 99 * 101 = | | 8) 100 * 100 - 1 * 1 = 9999 |
| 9) | 404 * 396 = | | 9) 400 * 400 - 4 * 4 = 159984 |
| 10) | 198 * 202 = | | 10) 200 * 200 - 2 * 2 = 39996 |
| 11) | 163 * 54 + 54 * 37 = | | 11) ( 163 + 37) * 54 = 10800 |
| 12) | 60 * 265 - 65 * 60 = | | 12) ( 265 - 65) * 60 = 12000 |
| 13) | 41 * 36 + 41 * 164 = | | 13) ( 164 + 36) * 41 = 8200 |
| 14) | 142 * 28 + 58 * 28 = | | 14) ( 142 + 58) * 28 = 5600 |
| 15) | 55 * 140 - 55 * 40 = | | 15) ( 140 - 40) * 55 = 5500 |
| 16) | 43 * 255 - 43 * 55 = | | 16) ( 255 - 55) * 43 = 8600 |
| 17) | 48 * 74 + 52 * 74 = | | 17) ( 52 + 48) * 74 = 7400 |
| 18) | 157 * 90 + 90 * 43 = | | 18) ( 157 + 43) * 90 = 18000 |
| 19) | 151 * 67 + 67 * 49 = | | 19) ( 151 + 49) * 67 = 13400 |
| 20) | 60 * 152 + 60 * 48 = | | 20) ( 152 + 48) * 60 = 12000 |
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Score: ______________ | |
