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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Monday April 27 2026
10:27:44 PM | Monday April 27 2026
10:27:44 PMFlip Answers |
| 1) | 290 * 310 = | | 1) 300 * 300 - 10 * 10 = 89900 |
| 2) | 196 * 204 = | | 2) 200 * 200 - 4 * 4 = 39984 |
| 3) | 296 * 304 = | | 3) 300 * 300 - 4 * 4 = 89984 |
| 4) | 305 * 295 = | | 4) 300 * 300 - 5 * 5 = 89975 |
| 5) | 297 * 303 = | | 5) 300 * 300 - 3 * 3 = 89991 |
| 6) | 103 * 97 = | | 6) 100 * 100 - 3 * 3 = 9991 |
| 7) | 308 * 292 = | | 7) 300 * 300 - 8 * 8 = 89936 |
| 8) | 208 * 192 = | | 8) 200 * 200 - 8 * 8 = 39936 |
| 9) | 393 * 407 = | | 9) 400 * 400 - 7 * 7 = 159951 |
| 10) | 293 * 307 = | | 10) 300 * 300 - 7 * 7 = 89951 |
| 11) | 38 * 79 + 62 * 79 = | | 11) ( 38 + 62) * 79 = 7900 |
| 12) | 50 * 45 + 45 * 50 = | | 12) ( 50 + 50) * 45 = 4500 |
| 13) | 136 * 34 - 34 * 36 = | | 13) ( 136 - 36) * 34 = 3400 |
| 14) | 155 * 83 - 83 * 55 = | | 14) ( 155 - 55) * 83 = 8300 |
| 15) | 160 * 96 - 60 * 96 = | | 15) ( 160 - 60) * 96 = 9600 |
| 16) | 143 * 94 - 43 * 94 = | | 16) ( 143 - 43) * 94 = 9400 |
| 17) | 24 * 62 + 38 * 24 = | | 17) ( 38 + 62) * 24 = 2400 |
| 18) | 67 * 90 + 90 * 33 = | | 18) ( 33 + 67) * 90 = 9000 |
| 19) | 147 * 61 - 47 * 61 = | | 19) ( 147 - 47) * 61 = 6100 |
| 20) | 159 * 63 - 63 * 59 = | | 20) ( 159 - 59) * 63 = 6300 |
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Score: ______________ | |
