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 July 02 2026
08:32:00 PM | Thursday July 02 2026
08:32:00 PMFlip Answers |
| 1) | 191 * 209 = | | 1) 200 * 200 - 9 * 9 = 39919 |
| 2) | 210 * 190 = | | 2) 200 * 200 - 10 * 10 = 39900 |
| 3) | 201 * 199 = | | 3) 200 * 200 - 1 * 1 = 39999 |
| 4) | 101 * 99 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 308 * 292 = | | 5) 300 * 300 - 8 * 8 = 89936 |
| 6) | 91 * 109 = | | 6) 100 * 100 - 9 * 9 = 9919 |
| 7) | 297 * 303 = | | 7) 300 * 300 - 3 * 3 = 89991 |
| 8) | 291 * 309 = | | 8) 300 * 300 - 9 * 9 = 89919 |
| 9) | 92 * 108 = | | 9) 100 * 100 - 8 * 8 = 9936 |
| 10) | 99 * 101 = | | 10) 100 * 100 - 1 * 1 = 9999 |
| 11) | 39 * 249 - 49 * 39 = | | 11) ( 249 - 49) * 39 = 7800 |
| 12) | 157 * 27 - 27 * 57 = | | 12) ( 157 - 57) * 27 = 2700 |
| 13) | 38 * 80 + 62 * 80 = | | 13) ( 38 + 62) * 80 = 8000 |
| 14) | 55 * 70 + 45 * 70 = | | 14) ( 55 + 45) * 70 = 7000 |
| 15) | 61 * 48 + 39 * 48 = | | 15) ( 39 + 61) * 48 = 4800 |
| 16) | 70 * 69 + 131 * 70 = | | 16) ( 131 + 69) * 70 = 14000 |
| 17) | 56 * 65 + 135 * 56 = | | 17) ( 135 + 65) * 56 = 11200 |
| 18) | 77 * 32 + 77 * 68 = | | 18) ( 32 + 68) * 77 = 7700 |
| 19) | 265 * 60 - 60 * 65 = | | 19) ( 265 - 65) * 60 = 12000 |
| 20) | 244 * 29 - 29 * 44 = | | 20) ( 244 - 44) * 29 = 5800 |
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Score: ______________ | |
