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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Friday January 30 2026
08:42:32 PM | Friday January 30 2026
08:42:32 PMFlip Answers |
| 1) | 93 * 107 = | | 1) 100 * 100 - 7 * 7 = 9951 |
| 2) | 399 * 401 = | | 2) 400 * 400 - 1 * 1 = 159999 |
| 3) | 198 * 202 = | | 3) 200 * 200 - 2 * 2 = 39996 |
| 4) | 109 * 91 = | | 4) 100 * 100 - 9 * 9 = 9919 |
| 5) | 404 * 396 = | | 5) 400 * 400 - 4 * 4 = 159984 |
| 6) | 105 * 95 = | | 6) 100 * 100 - 5 * 5 = 9975 |
| 7) | 91 * 109 = | | 7) 100 * 100 - 9 * 9 = 9919 |
| 8) | 308 * 292 = | | 8) 300 * 300 - 8 * 8 = 89936 |
| 9) | 98 * 102 = | | 9) 100 * 100 - 2 * 2 = 9996 |
| 10) | 201 * 199 = | | 10) 200 * 200 - 1 * 1 = 39999 |
| 11) | 237 * 35 - 35 * 37 = | | 11) ( 237 - 37) * 35 = 7000 |
| 12) | 65 * 143 + 65 * 57 = | | 12) ( 143 + 57) * 65 = 13000 |
| 13) | 45 * 139 - 39 * 45 = | | 13) ( 139 - 39) * 45 = 4500 |
| 14) | 57 * 78 + 78 * 143 = | | 14) ( 143 + 57) * 78 = 15600 |
| 15) | 93 * 173 - 93 * 73 = | | 15) ( 173 - 73) * 93 = 9300 |
| 16) | 27 * 169 - 69 * 27 = | | 16) ( 169 - 69) * 27 = 2700 |
| 17) | 61 * 91 + 91 * 139 = | | 17) ( 139 + 61) * 91 = 18200 |
| 18) | 41 * 47 + 53 * 41 = | | 18) ( 53 + 47) * 41 = 4100 |
| 19) | 41 * 236 - 36 * 41 = | | 19) ( 236 - 36) * 41 = 8200 |
| 20) | 42 * 63 + 37 * 42 = | | 20) ( 37 + 63) * 42 = 4200 |
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Score: ______________ | |
