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
|
|
Friday July 17 2026
11:59:13 AM | Friday July 17 2026
11:59:13 AMFlip Answers |
| 1) | 301 * 299 = | | 1) 300 * 300 - 1 * 1 = 89999 |
| 2) | 301 * 299 = | | 2) 300 * 300 - 1 * 1 = 89999 |
| 3) | 103 * 97 = | | 3) 100 * 100 - 3 * 3 = 9991 |
| 4) | 391 * 409 = | | 4) 400 * 400 - 9 * 9 = 159919 |
| 5) | 407 * 393 = | | 5) 400 * 400 - 7 * 7 = 159951 |
| 6) | 205 * 195 = | | 6) 200 * 200 - 5 * 5 = 39975 |
| 7) | 310 * 290 = | | 7) 300 * 300 - 10 * 10 = 89900 |
| 8) | 206 * 194 = | | 8) 200 * 200 - 6 * 6 = 39964 |
| 9) | 302 * 298 = | | 9) 300 * 300 - 2 * 2 = 89996 |
| 10) | 109 * 91 = | | 10) 100 * 100 - 9 * 9 = 9919 |
| 11) | 142 * 81 - 42 * 81 = | | 11) ( 142 - 42) * 81 = 8100 |
| 12) | 76 * 58 + 42 * 76 = | | 12) ( 42 + 58) * 76 = 7600 |
| 13) | 62 * 245 - 45 * 62 = | | 13) ( 245 - 45) * 62 = 12400 |
| 14) | 96 * 270 - 96 * 70 = | | 14) ( 270 - 70) * 96 = 19200 |
| 15) | 48 * 147 - 47 * 48 = | | 15) ( 147 - 47) * 48 = 4800 |
| 16) | 66 * 251 - 66 * 51 = | | 16) ( 251 - 51) * 66 = 13200 |
| 17) | 71 * 265 - 71 * 65 = | | 17) ( 265 - 65) * 71 = 14200 |
| 18) | 43 * 96 + 96 * 57 = | | 18) ( 43 + 57) * 96 = 9600 |
| 19) | 54 * 66 + 66 * 46 = | | 19) ( 46 + 54) * 66 = 6600 |
| 20) | 32 * 162 + 38 * 32 = | | 20) ( 162 + 38) * 32 = 6400 |
|
Score: ______________ | |
