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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Saturday August 15 2026
03:31:04 PM | Saturday August 15 2026
03:31:04 PMFlip Answers |
| 1) | 207 * 193 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 391 * 409 = | | 2) 400 * 400 - 9 * 9 = 159919 |
| 3) | 205 * 195 = | | 3) 200 * 200 - 5 * 5 = 39975 |
| 4) | 101 * 99 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 93 * 107 = | | 5) 100 * 100 - 7 * 7 = 9951 |
| 6) | 192 * 208 = | | 6) 200 * 200 - 8 * 8 = 39936 |
| 7) | 310 * 290 = | | 7) 300 * 300 - 10 * 10 = 89900 |
| 8) | 108 * 92 = | | 8) 100 * 100 - 8 * 8 = 9936 |
| 9) | 303 * 297 = | | 9) 300 * 300 - 3 * 3 = 89991 |
| 10) | 298 * 302 = | | 10) 300 * 300 - 2 * 2 = 89996 |
| 11) | 53 * 260 - 60 * 53 = | | 11) ( 260 - 60) * 53 = 10600 |
| 12) | 125 * 77 + 77 * 75 = | | 12) ( 125 + 75) * 77 = 15400 |
| 13) | 149 * 25 - 25 * 49 = | | 13) ( 149 - 49) * 25 = 2500 |
| 14) | 145 * 50 + 50 * 55 = | | 14) ( 145 + 55) * 50 = 10000 |
| 15) | 28 * 46 + 28 * 154 = | | 15) ( 154 + 46) * 28 = 5600 |
| 16) | 246 * 65 - 65 * 46 = | | 16) ( 246 - 46) * 65 = 13000 |
| 17) | 59 * 151 + 59 * 49 = | | 17) ( 151 + 49) * 59 = 11800 |
| 18) | 25 * 74 + 74 * 75 = | | 18) ( 25 + 75) * 74 = 7400 |
| 19) | 54 * 51 + 54 * 49 = | | 19) ( 51 + 49) * 54 = 5400 |
| 20) | 265 * 50 - 50 * 65 = | | 20) ( 265 - 65) * 50 = 10000 |
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Score: ______________ | |
