计算. (l)−43÷(−2)2×1/5; (2)−1.53×0.75+0.53×3/4−3.4×0.75; (3)−(1−0.5)÷1/3×[2+(−4)2]; (4)(−5)3×(−3/5)+32÷(−22)×(−11/4).

问题描述:

计算.
(l)43÷(−2)2×

1
5

(2)−1.53×0.75+0.53×
3
4
−3.4×0.75

(3)−(1−0.5)÷
1
3
×[2+(−4)2]

(4)(−5)3×(−
3
5
)+32÷(−22)×(−1
1
4
)

(1)原式=-64×

1
4
×
1
5
=-
16
5

(2)原式=0.75×(-1.53+0.53-3.4)=3.3;
(3)原式=-
1
2
×3×18=-27;
(4)原式=75+32×(-
1
4
)×(-
5
4
)=75+10=85.