能用简便方法计算的用简便方法计算. 25×1.25×32 (3.75+4.1+2.15)×9.8 5400-2940÷28×27 (20.2×0.4+7.88)÷4.2 (4/5+1/4)÷7/3+7/10 10÷[8/3-(5/13÷5/
问题描述:
能用简便方法计算的用简便方法计算.
25×1.25×32
(3.75+4.1+2.15)×9.8
5400-2940÷28×27
(20.2×0.4+7.88)÷4.2
(
+4 5
)÷1 4
+7 3
7 10
10÷[
-(8 3
÷5 13
+5 26
)].2 5
答
(1)25×1.25×32,=(25×4)×(1.25×8),=100×10,=1000;(2)(3.75+4.1+2.15)×9.8,=10×9.8,=98;(3)5400-2940÷28×27,=5400-105×27,=5400-2835,=2565;(4)(20.2×0.4+7.88)÷4.2,=(8.08...