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 February 21 2026
11:02:20 PM | Saturday February 21 2026
11:02:20 PMFlip Answers |
| 1) | 198 * 202 = | | 1) 200 * 200 - 2 * 2 = 39996 |
| 2) | 404 * 396 = | | 2) 400 * 400 - 4 * 4 = 159984 |
| 3) | 290 * 310 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 97 * 103 = | | 4) 100 * 100 - 3 * 3 = 9991 |
| 5) | 406 * 394 = | | 5) 400 * 400 - 6 * 6 = 159964 |
| 6) | 297 * 303 = | | 6) 300 * 300 - 3 * 3 = 89991 |
| 7) | 206 * 194 = | | 7) 200 * 200 - 6 * 6 = 39964 |
| 8) | 192 * 208 = | | 8) 200 * 200 - 8 * 8 = 39936 |
| 9) | 91 * 109 = | | 9) 100 * 100 - 9 * 9 = 9919 |
| 10) | 293 * 307 = | | 10) 300 * 300 - 7 * 7 = 89951 |
| 11) | 249 * 71 - 71 * 49 = | | 11) ( 249 - 49) * 71 = 14200 |
| 12) | 45 * 82 + 155 * 82 = | | 12) ( 155 + 45) * 82 = 16400 |
| 13) | 75 * 24 + 24 * 25 = | | 13) ( 25 + 75) * 24 = 2400 |
| 14) | 28 * 60 + 140 * 28 = | | 14) ( 140 + 60) * 28 = 5600 |
| 15) | 50 * 50 + 50 * 50 = | | 15) ( 50 + 50) * 50 = 5000 |
| 16) | 80 * 67 + 33 * 80 = | | 16) ( 33 + 67) * 80 = 8000 |
| 17) | 239 * 26 - 26 * 39 = | | 17) ( 239 - 39) * 26 = 5200 |
| 18) | 43 * 141 - 41 * 43 = | | 18) ( 141 - 41) * 43 = 4300 |
| 19) | 29 * 28 + 71 * 28 = | | 19) ( 29 + 71) * 28 = 2800 |
| 20) | 137 * 71 + 63 * 71 = | | 20) ( 137 + 63) * 71 = 14200 |
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Score: ______________ | |
