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 September 16 2026
08:54:35 AM | Wednesday September 16 2026
08:54:35 AMFlip Answers |
| 1) | 197 * 203 = | | 1) 200 * 200 - 3 * 3 = 39991 |
| 2) | 205 * 195 = | | 2) 200 * 200 - 5 * 5 = 39975 |
| 3) | 203 * 197 = | | 3) 200 * 200 - 3 * 3 = 39991 |
| 4) | 201 * 199 = | | 4) 200 * 200 - 1 * 1 = 39999 |
| 5) | 410 * 390 = | | 5) 400 * 400 - 10 * 10 = 159900 |
| 6) | 206 * 194 = | | 6) 200 * 200 - 6 * 6 = 39964 |
| 7) | 394 * 406 = | | 7) 400 * 400 - 6 * 6 = 159964 |
| 8) | 290 * 310 = | | 8) 300 * 300 - 10 * 10 = 89900 |
| 9) | 407 * 393 = | | 9) 400 * 400 - 7 * 7 = 159951 |
| 10) | 405 * 395 = | | 10) 400 * 400 - 5 * 5 = 159975 |
| 11) | 58 * 69 + 69 * 42 = | | 11) ( 42 + 58) * 69 = 6900 |
| 12) | 46 * 58 + 42 * 46 = | | 12) ( 58 + 42) * 46 = 4600 |
| 13) | 249 * 97 - 97 * 49 = | | 13) ( 249 - 49) * 97 = 19400 |
| 14) | 45 * 259 - 59 * 45 = | | 14) ( 259 - 59) * 45 = 9000 |
| 15) | 69 * 45 + 31 * 45 = | | 15) ( 31 + 69) * 45 = 4500 |
| 16) | 162 * 88 - 88 * 62 = | | 16) ( 162 - 62) * 88 = 8800 |
| 17) | 76 * 129 + 71 * 76 = | | 17) ( 129 + 71) * 76 = 15200 |
| 18) | 140 * 58 + 58 * 60 = | | 18) ( 140 + 60) * 58 = 11600 |
| 19) | 70 * 240 - 70 * 40 = | | 19) ( 240 - 40) * 70 = 14000 |
| 20) | 72 * 72 + 72 * 28 = | | 20) ( 28 + 72) * 72 = 7200 |
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Score: ______________ | |
