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 November 27 2025
01:14:04 PM | Thursday November 27 2025
01:14:04 PMFlip Answers |
| 1) | 91 * 109 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 201 * 199 = | | 2) 200 * 200 - 1 * 1 = 39999 |
| 3) | 209 * 191 = | | 3) 200 * 200 - 9 * 9 = 39919 |
| 4) | 408 * 392 = | | 4) 400 * 400 - 8 * 8 = 159936 |
| 5) | 299 * 301 = | | 5) 300 * 300 - 1 * 1 = 89999 |
| 6) | 301 * 299 = | | 6) 300 * 300 - 1 * 1 = 89999 |
| 7) | 406 * 394 = | | 7) 400 * 400 - 6 * 6 = 159964 |
| 8) | 198 * 202 = | | 8) 200 * 200 - 2 * 2 = 39996 |
| 9) | 307 * 293 = | | 9) 300 * 300 - 7 * 7 = 89951 |
| 10) | 99 * 101 = | | 10) 100 * 100 - 1 * 1 = 9999 |
| 11) | 55 * 96 + 96 * 45 = | | 11) ( 55 + 45) * 96 = 9600 |
| 12) | 66 * 254 - 54 * 66 = | | 12) ( 254 - 54) * 66 = 13200 |
| 13) | 25 * 174 - 25 * 74 = | | 13) ( 174 - 74) * 25 = 2500 |
| 14) | 70 * 165 + 35 * 70 = | | 14) ( 165 + 35) * 70 = 14000 |
| 15) | 236 * 45 - 45 * 36 = | | 15) ( 236 - 36) * 45 = 9000 |
| 16) | 83 * 142 - 42 * 83 = | | 16) ( 142 - 42) * 83 = 8300 |
| 17) | 275 * 67 - 67 * 75 = | | 17) ( 275 - 75) * 67 = 13400 |
| 18) | 171 * 86 - 86 * 71 = | | 18) ( 171 - 71) * 86 = 8600 |
| 19) | 37 * 32 + 32 * 63 = | | 19) ( 63 + 37) * 32 = 3200 |
| 20) | 71 * 46 + 129 * 46 = | | 20) ( 129 + 71) * 46 = 9200 |
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Score: ______________ | |
