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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Sunday July 19 2026
01:19:49 PM | Sunday July 19 2026
01:19:49 PMFlip Answers |
| 1) | 105 * 95 = | | 1) 100 * 100 - 5 * 5 = 9975 |
| 2) | 291 * 309 = | | 2) 300 * 300 - 9 * 9 = 89919 |
| 3) | 105 * 95 = | | 3) 100 * 100 - 5 * 5 = 9975 |
| 4) | 407 * 393 = | | 4) 400 * 400 - 7 * 7 = 159951 |
| 5) | 201 * 199 = | | 5) 200 * 200 - 1 * 1 = 39999 |
| 6) | 207 * 193 = | | 6) 200 * 200 - 7 * 7 = 39951 |
| 7) | 191 * 209 = | | 7) 200 * 200 - 9 * 9 = 39919 |
| 8) | 198 * 202 = | | 8) 200 * 200 - 2 * 2 = 39996 |
| 9) | 191 * 209 = | | 9) 200 * 200 - 9 * 9 = 39919 |
| 10) | 403 * 397 = | | 10) 400 * 400 - 3 * 3 = 159991 |
| 11) | 258 * 32 - 58 * 32 = | | 11) ( 258 - 58) * 32 = 6400 |
| 12) | 152 * 33 + 48 * 33 = | | 12) ( 152 + 48) * 33 = 6600 |
| 13) | 73 * 256 - 56 * 73 = | | 13) ( 256 - 56) * 73 = 14600 |
| 14) | 73 * 30 + 30 * 127 = | | 14) ( 127 + 73) * 30 = 6000 |
| 15) | 164 * 40 + 40 * 36 = | | 15) ( 164 + 36) * 40 = 8000 |
| 16) | 147 * 86 - 47 * 86 = | | 16) ( 147 - 47) * 86 = 8600 |
| 17) | 147 * 76 + 53 * 76 = | | 17) ( 147 + 53) * 76 = 15200 |
| 18) | 21 * 154 - 54 * 21 = | | 18) ( 154 - 54) * 21 = 2100 |
| 19) | 245 * 82 - 82 * 45 = | | 19) ( 245 - 45) * 82 = 16400 |
| 20) | 155 * 21 - 55 * 21 = | | 20) ( 155 - 55) * 21 = 2100 |
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Score: ______________ | |
