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 May 15 2026
03:27:36 PM | Friday May 15 2026
03:27:36 PMFlip Answers |
| 1) | 198 * 202 = | | 1) 200 * 200 - 2 * 2 = 39996 |
| 2) | 208 * 192 = | | 2) 200 * 200 - 8 * 8 = 39936 |
| 3) | 294 * 306 = | | 3) 300 * 300 - 6 * 6 = 89964 |
| 4) | 201 * 199 = | | 4) 200 * 200 - 1 * 1 = 39999 |
| 5) | 101 * 99 = | | 5) 100 * 100 - 1 * 1 = 9999 |
| 6) | 90 * 110 = | | 6) 100 * 100 - 10 * 10 = 9900 |
| 7) | 210 * 190 = | | 7) 200 * 200 - 10 * 10 = 39900 |
| 8) | 302 * 298 = | | 8) 300 * 300 - 2 * 2 = 89996 |
| 9) | 91 * 109 = | | 9) 100 * 100 - 9 * 9 = 9919 |
| 10) | 396 * 404 = | | 10) 400 * 400 - 4 * 4 = 159984 |
| 11) | 61 * 93 + 39 * 93 = | | 11) ( 61 + 39) * 93 = 9300 |
| 12) | 79 * 50 + 79 * 50 = | | 12) ( 50 + 50) * 79 = 7900 |
| 13) | 136 * 92 + 64 * 92 = | | 13) ( 136 + 64) * 92 = 18400 |
| 14) | 61 * 54 + 54 * 39 = | | 14) ( 39 + 61) * 54 = 5400 |
| 15) | 42 * 21 + 158 * 21 = | | 15) ( 158 + 42) * 21 = 4200 |
| 16) | 25 * 171 - 71 * 25 = | | 16) ( 171 - 71) * 25 = 2500 |
| 17) | 48 * 157 - 48 * 57 = | | 17) ( 157 - 57) * 48 = 4800 |
| 18) | 241 * 36 - 36 * 41 = | | 18) ( 241 - 41) * 36 = 7200 |
| 19) | 88 * 38 + 88 * 62 = | | 19) ( 38 + 62) * 88 = 8800 |
| 20) | 65 * 133 + 67 * 65 = | | 20) ( 133 + 67) * 65 = 13000 |
|
Score: ______________ | |
