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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Friday October 31 2025
01:42:15 PM | Friday October 31 2025
01:42:15 PMFlip Answers |
| 1) | 305 * 295 = | | 1) 300 * 300 - 5 * 5 = 89975 |
| 2) | 192 * 208 = | | 2) 200 * 200 - 8 * 8 = 39936 |
| 3) | 109 * 91 = | | 3) 100 * 100 - 9 * 9 = 9919 |
| 4) | 206 * 194 = | | 4) 200 * 200 - 6 * 6 = 39964 |
| 5) | 407 * 393 = | | 5) 400 * 400 - 7 * 7 = 159951 |
| 6) | 391 * 409 = | | 6) 400 * 400 - 9 * 9 = 159919 |
| 7) | 99 * 101 = | | 7) 100 * 100 - 1 * 1 = 9999 |
| 8) | 397 * 403 = | | 8) 400 * 400 - 3 * 3 = 159991 |
| 9) | 191 * 209 = | | 9) 200 * 200 - 9 * 9 = 39919 |
| 10) | 199 * 201 = | | 10) 200 * 200 - 1 * 1 = 39999 |
| 11) | 137 * 77 - 77 * 37 = | | 11) ( 137 - 37) * 77 = 7700 |
| 12) | 23 * 63 + 23 * 137 = | | 12) ( 137 + 63) * 23 = 4600 |
| 13) | 39 * 87 + 161 * 87 = | | 13) ( 161 + 39) * 87 = 17400 |
| 14) | 138 * 72 + 72 * 62 = | | 14) ( 138 + 62) * 72 = 14400 |
| 15) | 37 * 159 + 37 * 41 = | | 15) ( 159 + 41) * 37 = 7400 |
| 16) | 43 * 150 - 43 * 50 = | | 16) ( 150 - 50) * 43 = 4300 |
| 17) | 29 * 265 - 65 * 29 = | | 17) ( 265 - 65) * 29 = 5800 |
| 18) | 63 * 254 - 54 * 63 = | | 18) ( 254 - 54) * 63 = 12600 |
| 19) | 46 * 86 + 54 * 86 = | | 19) ( 54 + 46) * 86 = 8600 |
| 20) | 40 * 152 - 40 * 52 = | | 20) ( 152 - 52) * 40 = 4000 |
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Score: ______________ | |
