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 June 20 2026
07:32:24 AM | Saturday June 20 2026
07:32:24 AMFlip Answers |
| 1) | 309 * 291 = | | 1) 300 * 300 - 9 * 9 = 89919 |
| 2) | 299 * 301 = | | 2) 300 * 300 - 1 * 1 = 89999 |
| 3) | 208 * 192 = | | 3) 200 * 200 - 8 * 8 = 39936 |
| 4) | 190 * 210 = | | 4) 200 * 200 - 10 * 10 = 39900 |
| 5) | 395 * 405 = | | 5) 400 * 400 - 5 * 5 = 159975 |
| 6) | 304 * 296 = | | 6) 300 * 300 - 4 * 4 = 89984 |
| 7) | 201 * 199 = | | 7) 200 * 200 - 1 * 1 = 39999 |
| 8) | 403 * 397 = | | 8) 400 * 400 - 3 * 3 = 159991 |
| 9) | 197 * 203 = | | 9) 200 * 200 - 3 * 3 = 39991 |
| 10) | 405 * 395 = | | 10) 400 * 400 - 5 * 5 = 159975 |
| 11) | 74 * 135 + 74 * 65 = | | 11) ( 135 + 65) * 74 = 14800 |
| 12) | 52 * 249 - 52 * 49 = | | 12) ( 249 - 49) * 52 = 10400 |
| 13) | 89 * 260 - 60 * 89 = | | 13) ( 260 - 60) * 89 = 17800 |
| 14) | 62 * 238 - 62 * 38 = | | 14) ( 238 - 38) * 62 = 12400 |
| 15) | 30 * 60 + 30 * 140 = | | 15) ( 140 + 60) * 30 = 6000 |
| 16) | 63 * 171 - 71 * 63 = | | 16) ( 171 - 71) * 63 = 6300 |
| 17) | 81 * 156 - 81 * 56 = | | 17) ( 156 - 56) * 81 = 8100 |
| 18) | 144 * 86 - 44 * 86 = | | 18) ( 144 - 44) * 86 = 8600 |
| 19) | 25 * 244 - 44 * 25 = | | 19) ( 244 - 44) * 25 = 5000 |
| 20) | 65 * 82 + 35 * 82 = | | 20) ( 35 + 65) * 82 = 8200 |
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Score: ______________ | |
