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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Sunday October 18 2026
12:30:31 AM | Sunday October 18 2026
12:30:31 AMFlip Answers |
| 1) | 207 * 193 = | | 1) 200 * 200 - 7 * 7 = 39951 |
| 2) | 301 * 299 = | | 2) 300 * 300 - 1 * 1 = 89999 |
| 3) | 97 * 103 = | | 3) 100 * 100 - 3 * 3 = 9991 |
| 4) | 302 * 298 = | | 4) 300 * 300 - 2 * 2 = 89996 |
| 5) | 207 * 193 = | | 5) 200 * 200 - 7 * 7 = 39951 |
| 6) | 401 * 399 = | | 6) 400 * 400 - 1 * 1 = 159999 |
| 7) | 291 * 309 = | | 7) 300 * 300 - 9 * 9 = 89919 |
| 8) | 198 * 202 = | | 8) 200 * 200 - 2 * 2 = 39996 |
| 9) | 394 * 406 = | | 9) 400 * 400 - 6 * 6 = 159964 |
| 10) | 392 * 408 = | | 10) 400 * 400 - 8 * 8 = 159936 |
| 11) | 54 * 130 + 54 * 70 = | | 11) ( 130 + 70) * 54 = 10800 |
| 12) | 62 * 275 - 75 * 62 = | | 12) ( 275 - 75) * 62 = 12400 |
| 13) | 61 * 50 + 39 * 50 = | | 13) ( 39 + 61) * 50 = 5000 |
| 14) | 79 * 69 + 31 * 79 = | | 14) ( 31 + 69) * 79 = 7900 |
| 15) | 40 * 70 + 60 * 70 = | | 15) ( 40 + 60) * 70 = 7000 |
| 16) | 73 * 52 + 52 * 27 = | | 16) ( 27 + 73) * 52 = 5200 |
| 17) | 247 * 48 - 47 * 48 = | | 17) ( 247 - 47) * 48 = 9600 |
| 18) | 51 * 63 + 51 * 37 = | | 18) ( 37 + 63) * 51 = 5100 |
| 19) | 51 * 145 - 51 * 45 = | | 19) ( 145 - 45) * 51 = 5100 |
| 20) | 91 * 235 - 35 * 91 = | | 20) ( 235 - 35) * 91 = 18200 |
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Score: ______________ | |
