Tính bằng cách hợp lý: 2155 - (174 + 2155) + (-68 + 174)
Tính bằng cách hợp lý:
1, 2155- (174+2155)+ (-68+174)
2, -25 x 72 +25 x 21 - 49 x25
3, 35x (14-23) - 23 x (14-35)
4, 8154- (674 +8154) + (-98 + 674)
5, -25 x 21+25 x 72 + 49 x 25
6, 27 x (13-16) - 16 x (13 - 27)
7, -1911 - (1234 - 1911)
8, 156 x 72 + 28 x 156
9, 32x (-39) + 16. (-22)
10, -1945 - (567 - 1945)
11, 184x 33 + 67x 184
12, 44x (-36) + 22x ( -28)
1, 2155- (174+2155)+ (-68+174)
2, -25 x 72 +25 x 21 - 49 x25
3, 35x (14-23) - 23 x (14-35)
4, 8154- (674 +8154) + (-98 + 674)
5, -25 x 21+25 x 72 + 49 x 25
6, 27 x (13-16) - 16 x (13 - 27)
7, -1911 - (1234 - 1911)
8, 156 x 72 + 28 x 156
9, 32x (-39) + 16. (-22)
10, -1945 - (567 - 1945)
11, 184x 33 + 67x 184
12, 44x (-36) + 22x ( -28)