Math Main Page => Exercises - Math III
|
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
|
|
Thursday September 24 2026
10:26:20 PM | Thursday September 24 2026
10:26:20 PMFlip Answers |
| 1) | 197 * 203 = | | 1) 200 * 200 - 3 * 3 = 39991 |
| 2) | 290 * 310 = | | 2) 300 * 300 - 10 * 10 = 89900 |
| 3) | 205 * 195 = | | 3) 200 * 200 - 5 * 5 = 39975 |
| 4) | 408 * 392 = | | 4) 400 * 400 - 8 * 8 = 159936 |
| 5) | 205 * 195 = | | 5) 200 * 200 - 5 * 5 = 39975 |
| 6) | 393 * 407 = | | 6) 400 * 400 - 7 * 7 = 159951 |
| 7) | 98 * 102 = | | 7) 100 * 100 - 2 * 2 = 9996 |
| 8) | 310 * 290 = | | 8) 300 * 300 - 10 * 10 = 89900 |
| 9) | 391 * 409 = | | 9) 400 * 400 - 9 * 9 = 159919 |
| 10) | 90 * 110 = | | 10) 100 * 100 - 10 * 10 = 9900 |
| 11) | 255 * 46 - 46 * 55 = | | 11) ( 255 - 55) * 46 = 9200 |
| 12) | 62 * 167 - 67 * 62 = | | 12) ( 167 - 67) * 62 = 6200 |
| 13) | 146 * 86 + 54 * 86 = | | 13) ( 146 + 54) * 86 = 17200 |
| 14) | 74 * 164 - 74 * 64 = | | 14) ( 164 - 64) * 74 = 7400 |
| 15) | 59 * 144 - 59 * 44 = | | 15) ( 144 - 44) * 59 = 5900 |
| 16) | 92 * 138 - 92 * 38 = | | 16) ( 138 - 38) * 92 = 9200 |
| 17) | 60 * 150 + 50 * 60 = | | 17) ( 150 + 50) * 60 = 12000 |
| 18) | 94 * 139 + 94 * 61 = | | 18) ( 139 + 61) * 94 = 18800 |
| 19) | 56 * 63 + 63 * 44 = | | 19) ( 56 + 44) * 63 = 6300 |
| 20) | 45 * 242 - 42 * 45 = | | 20) ( 242 - 42) * 45 = 9000 |
|
Score: ______________ | |
