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 February 12 2026
11:26:06 AM | Thursday February 12 2026
11:26:06 AMFlip Answers |
| 1) | 91 * 109 = | | 1) 100 * 100 - 9 * 9 = 9919 |
| 2) | 291 * 309 = | | 2) 300 * 300 - 9 * 9 = 89919 |
| 3) | 204 * 196 = | | 3) 200 * 200 - 4 * 4 = 39984 |
| 4) | 193 * 207 = | | 4) 200 * 200 - 7 * 7 = 39951 |
| 5) | 299 * 301 = | | 5) 300 * 300 - 1 * 1 = 89999 |
| 6) | 191 * 209 = | | 6) 200 * 200 - 9 * 9 = 39919 |
| 7) | 96 * 104 = | | 7) 100 * 100 - 4 * 4 = 9984 |
| 8) | 210 * 190 = | | 8) 200 * 200 - 10 * 10 = 39900 |
| 9) | 110 * 90 = | | 9) 100 * 100 - 10 * 10 = 9900 |
| 10) | 307 * 293 = | | 10) 300 * 300 - 7 * 7 = 89951 |
| 11) | 163 * 83 + 37 * 83 = | | 11) ( 163 + 37) * 83 = 16600 |
| 12) | 160 * 38 + 40 * 38 = | | 12) ( 160 + 40) * 38 = 7600 |
| 13) | 38 * 163 - 38 * 63 = | | 13) ( 163 - 63) * 38 = 3800 |
| 14) | 156 * 50 + 50 * 44 = | | 14) ( 156 + 44) * 50 = 10000 |
| 15) | 66 * 164 - 66 * 64 = | | 15) ( 164 - 64) * 66 = 6600 |
| 16) | 67 * 242 - 42 * 67 = | | 16) ( 242 - 42) * 67 = 13400 |
| 17) | 64 * 53 + 53 * 36 = | | 17) ( 36 + 64) * 53 = 5300 |
| 18) | 38 * 43 + 62 * 43 = | | 18) ( 62 + 38) * 43 = 4300 |
| 19) | 79 * 265 - 65 * 79 = | | 19) ( 265 - 65) * 79 = 15800 |
| 20) | 85 * 62 + 85 * 38 = | | 20) ( 62 + 38) * 85 = 8500 |
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Score: ______________ | |
