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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Tuesday March 24 2026
01:02:01 PM | Tuesday March 24 2026
01:02:01 PMFlip Answers |
| 1) | 410 * 390 = | | 1) 400 * 400 - 10 * 10 = 159900 |
| 2) | 107 * 93 = | | 2) 100 * 100 - 7 * 7 = 9951 |
| 3) | 392 * 408 = | | 3) 400 * 400 - 8 * 8 = 159936 |
| 4) | 202 * 198 = | | 4) 200 * 200 - 2 * 2 = 39996 |
| 5) | 97 * 103 = | | 5) 100 * 100 - 3 * 3 = 9991 |
| 6) | 209 * 191 = | | 6) 200 * 200 - 9 * 9 = 39919 |
| 7) | 209 * 191 = | | 7) 200 * 200 - 9 * 9 = 39919 |
| 8) | 302 * 298 = | | 8) 300 * 300 - 2 * 2 = 89996 |
| 9) | 193 * 207 = | | 9) 200 * 200 - 7 * 7 = 39951 |
| 10) | 205 * 195 = | | 10) 200 * 200 - 5 * 5 = 39975 |
| 11) | 35 * 62 + 35 * 138 = | | 11) ( 138 + 62) * 35 = 7000 |
| 12) | 63 * 36 + 36 * 37 = | | 12) ( 63 + 37) * 36 = 3600 |
| 13) | 47 * 163 - 63 * 47 = | | 13) ( 163 - 63) * 47 = 4700 |
| 14) | 269 * 62 - 62 * 69 = | | 14) ( 269 - 69) * 62 = 12400 |
| 15) | 160 * 32 + 32 * 40 = | | 15) ( 160 + 40) * 32 = 6400 |
| 16) | 152 * 35 - 35 * 52 = | | 16) ( 152 - 52) * 35 = 3500 |
| 17) | 44 * 72 + 72 * 56 = | | 17) ( 56 + 44) * 72 = 7200 |
| 18) | 75 * 245 - 45 * 75 = | | 18) ( 245 - 45) * 75 = 15000 |
| 19) | 80 * 36 + 164 * 80 = | | 19) ( 164 + 36) * 80 = 16000 |
| 20) | 91 * 67 + 33 * 91 = | | 20) ( 33 + 67) * 91 = 9100 |
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Score: ______________ | |
