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 May 24 2026
05:25:14 PM | Sunday May 24 2026
05:25:14 PMFlip Answers |
| 1) | 298 * 302 = | | 1) 300 * 300 - 2 * 2 = 89996 |
| 2) | 390 * 410 = | | 2) 400 * 400 - 10 * 10 = 159900 |
| 3) | 290 * 310 = | | 3) 300 * 300 - 10 * 10 = 89900 |
| 4) | 101 * 99 = | | 4) 100 * 100 - 1 * 1 = 9999 |
| 5) | 210 * 190 = | | 5) 200 * 200 - 10 * 10 = 39900 |
| 6) | 103 * 97 = | | 6) 100 * 100 - 3 * 3 = 9991 |
| 7) | 93 * 107 = | | 7) 100 * 100 - 7 * 7 = 9951 |
| 8) | 410 * 390 = | | 8) 400 * 400 - 10 * 10 = 159900 |
| 9) | 190 * 210 = | | 9) 200 * 200 - 10 * 10 = 39900 |
| 10) | 293 * 307 = | | 10) 300 * 300 - 7 * 7 = 89951 |
| 11) | 149 * 40 - 40 * 49 = | | 11) ( 149 - 49) * 40 = 4000 |
| 12) | 36 * 52 + 52 * 64 = | | 12) ( 36 + 64) * 52 = 5200 |
| 13) | 48 * 127 + 48 * 73 = | | 13) ( 127 + 73) * 48 = 9600 |
| 14) | 242 * 29 - 29 * 42 = | | 14) ( 242 - 42) * 29 = 5800 |
| 15) | 64 * 64 + 36 * 64 = | | 15) ( 36 + 64) * 64 = 6400 |
| 16) | 38 * 43 + 38 * 57 = | | 16) ( 43 + 57) * 38 = 3800 |
| 17) | 68 * 42 + 42 * 32 = | | 17) ( 32 + 68) * 42 = 4200 |
| 18) | 162 * 65 - 62 * 65 = | | 18) ( 162 - 62) * 65 = 6500 |
| 19) | 274 * 77 - 77 * 74 = | | 19) ( 274 - 74) * 77 = 15400 |
| 20) | 85 * 150 - 50 * 85 = | | 20) ( 150 - 50) * 85 = 8500 |
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Score: ______________ | |
