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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Wednesday June 03 2026
03:35:19 PM | Wednesday June 03 2026
03:35:19 PMFlip Answers |
| 1) | 295 * 305 = | | 1) 300 * 300 - 5 * 5 = 89975 |
| 2) | 198 * 202 = | | 2) 200 * 200 - 2 * 2 = 39996 |
| 3) | 310 * 290 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 209 * 191 = | | 4) 200 * 200 - 9 * 9 = 39919 |
| 5) | 197 * 203 = | | 5) 200 * 200 - 3 * 3 = 39991 |
| 6) | 298 * 302 = | | 6) 300 * 300 - 2 * 2 = 89996 |
| 7) | 90 * 110 = | | 7) 100 * 100 - 10 * 10 = 9900 |
| 8) | 401 * 399 = | | 8) 400 * 400 - 1 * 1 = 159999 |
| 9) | 390 * 410 = | | 9) 400 * 400 - 10 * 10 = 159900 |
| 10) | 393 * 407 = | | 10) 400 * 400 - 7 * 7 = 159951 |
| 11) | 31 * 57 + 43 * 31 = | | 11) ( 57 + 43) * 31 = 3100 |
| 12) | 23 * 266 - 23 * 66 = | | 12) ( 266 - 66) * 23 = 4600 |
| 13) | 25 * 150 - 50 * 25 = | | 13) ( 150 - 50) * 25 = 2500 |
| 14) | 23 * 73 + 27 * 23 = | | 14) ( 27 + 73) * 23 = 2300 |
| 15) | 269 * 44 - 69 * 44 = | | 15) ( 269 - 69) * 44 = 8800 |
| 16) | 27 * 161 - 61 * 27 = | | 16) ( 161 - 61) * 27 = 2700 |
| 17) | 52 * 72 + 52 * 28 = | | 17) ( 28 + 72) * 52 = 5200 |
| 18) | 144 * 64 - 64 * 44 = | | 18) ( 144 - 44) * 64 = 6400 |
| 19) | 129 * 51 + 51 * 71 = | | 19) ( 129 + 71) * 51 = 10200 |
| 20) | 61 * 47 + 53 * 61 = | | 20) ( 47 + 53) * 61 = 6100 |
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Score: ______________ | |
