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 May 23 2026
07:47:19 AM | Saturday May 23 2026
07:47:19 AMFlip Answers |
| 1) | 302 * 298 = | | 1) 300 * 300 - 2 * 2 = 89996 |
| 2) | 203 * 197 = | | 2) 200 * 200 - 3 * 3 = 39991 |
| 3) | 393 * 407 = | | 3) 400 * 400 - 7 * 7 = 159951 |
| 4) | 109 * 91 = | | 4) 100 * 100 - 9 * 9 = 9919 |
| 5) | 398 * 402 = | | 5) 400 * 400 - 2 * 2 = 159996 |
| 6) | 293 * 307 = | | 6) 300 * 300 - 7 * 7 = 89951 |
| 7) | 309 * 291 = | | 7) 300 * 300 - 9 * 9 = 89919 |
| 8) | 297 * 303 = | | 8) 300 * 300 - 3 * 3 = 89991 |
| 9) | 106 * 94 = | | 9) 100 * 100 - 6 * 6 = 9964 |
| 10) | 190 * 210 = | | 10) 200 * 200 - 10 * 10 = 39900 |
| 11) | 21 * 34 + 66 * 21 = | | 11) ( 34 + 66) * 21 = 2100 |
| 12) | 136 * 79 + 64 * 79 = | | 12) ( 136 + 64) * 79 = 15800 |
| 13) | 37 * 27 + 27 * 63 = | | 13) ( 63 + 37) * 27 = 2700 |
| 14) | 47 * 237 - 37 * 47 = | | 14) ( 237 - 37) * 47 = 9400 |
| 15) | 68 * 69 + 68 * 31 = | | 15) ( 31 + 69) * 68 = 6800 |
| 16) | 50 * 41 + 41 * 50 = | | 16) ( 50 + 50) * 41 = 4100 |
| 17) | 173 * 75 - 73 * 75 = | | 17) ( 173 - 73) * 75 = 7500 |
| 18) | 88 * 62 + 38 * 88 = | | 18) ( 38 + 62) * 88 = 8800 |
| 19) | 163 * 37 - 37 * 63 = | | 19) ( 163 - 63) * 37 = 3700 |
| 20) | 46 * 71 + 71 * 54 = | | 20) ( 54 + 46) * 71 = 7100 |
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Score: ______________ | |
