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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Thursday May 07 2026
08:45:46 AM | Thursday May 07 2026
08:45:46 AMFlip Answers |
| 1) | 97 * 103 = | | 1) 100 * 100 - 3 * 3 = 9991 |
| 2) | 308 * 292 = | | 2) 300 * 300 - 8 * 8 = 89936 |
| 3) | 203 * 197 = | | 3) 200 * 200 - 3 * 3 = 39991 |
| 4) | 399 * 401 = | | 4) 400 * 400 - 1 * 1 = 159999 |
| 5) | 409 * 391 = | | 5) 400 * 400 - 9 * 9 = 159919 |
| 6) | 395 * 405 = | | 6) 400 * 400 - 5 * 5 = 159975 |
| 7) | 393 * 407 = | | 7) 400 * 400 - 7 * 7 = 159951 |
| 8) | 91 * 109 = | | 8) 100 * 100 - 9 * 9 = 9919 |
| 9) | 290 * 310 = | | 9) 300 * 300 - 10 * 10 = 89900 |
| 10) | 110 * 90 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 81 * 60 + 140 * 81 = | | 11) ( 140 + 60) * 81 = 16200 |
| 12) | 96 * 153 - 96 * 53 = | | 12) ( 153 - 53) * 96 = 9600 |
| 13) | 83 * 162 - 62 * 83 = | | 13) ( 162 - 62) * 83 = 8300 |
| 14) | 150 * 73 + 73 * 50 = | | 14) ( 150 + 50) * 73 = 14600 |
| 15) | 88 * 258 - 58 * 88 = | | 15) ( 258 - 58) * 88 = 17600 |
| 16) | 96 * 249 - 49 * 96 = | | 16) ( 249 - 49) * 96 = 19200 |
| 17) | 61 * 164 - 61 * 64 = | | 17) ( 164 - 64) * 61 = 6100 |
| 18) | 36 * 156 + 44 * 36 = | | 18) ( 156 + 44) * 36 = 7200 |
| 19) | 268 * 60 - 68 * 60 = | | 19) ( 268 - 68) * 60 = 12000 |
| 20) | 153 * 49 - 49 * 53 = | | 20) ( 153 - 53) * 49 = 4900 |
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Score: ______________ | |
