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 August 21 2026
03:18:48 AM | Friday August 21 2026
03:18:48 AMFlip Answers |
| 1) | 195 * 205 = | | 1) 200 * 200 - 5 * 5 = 39975 |
| 2) | 206 * 194 = | | 2) 200 * 200 - 6 * 6 = 39964 |
| 3) | 208 * 192 = | | 3) 200 * 200 - 8 * 8 = 39936 |
| 4) | 307 * 293 = | | 4) 300 * 300 - 7 * 7 = 89951 |
| 5) | 103 * 97 = | | 5) 100 * 100 - 3 * 3 = 9991 |
| 6) | 393 * 407 = | | 6) 400 * 400 - 7 * 7 = 159951 |
| 7) | 107 * 93 = | | 7) 100 * 100 - 7 * 7 = 9951 |
| 8) | 196 * 204 = | | 8) 200 * 200 - 4 * 4 = 39984 |
| 9) | 290 * 310 = | | 9) 300 * 300 - 10 * 10 = 89900 |
| 10) | 193 * 207 = | | 10) 200 * 200 - 7 * 7 = 39951 |
| 11) | 52 * 52 + 48 * 52 = | | 11) ( 48 + 52) * 52 = 5200 |
| 12) | 90 * 265 - 65 * 90 = | | 12) ( 265 - 65) * 90 = 18000 |
| 13) | 158 * 49 - 49 * 58 = | | 13) ( 158 - 58) * 49 = 4900 |
| 14) | 64 * 69 + 131 * 64 = | | 14) ( 131 + 69) * 64 = 12800 |
| 15) | 61 * 47 + 53 * 61 = | | 15) ( 53 + 47) * 61 = 6100 |
| 16) | 139 * 92 - 39 * 92 = | | 16) ( 139 - 39) * 92 = 9200 |
| 17) | 168 * 54 - 68 * 54 = | | 17) ( 168 - 68) * 54 = 5400 |
| 18) | 70 * 173 - 73 * 70 = | | 18) ( 173 - 73) * 70 = 7000 |
| 19) | 49 * 29 + 29 * 51 = | | 19) ( 51 + 49) * 29 = 2900 |
| 20) | 83 * 125 + 75 * 83 = | | 20) ( 125 + 75) * 83 = 16600 |
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Score: ______________ | |
