问题
解答题
脱式计算 32×0.16×2.5×1.25 6.4×4.2-4.2×
(0.3+
9÷[1-(
|
答案
(1)32×0.16×2.5×1.25,
=8×4×0.16×2.5×1.25,
=(8×1.25)×(4×2.5)×0.16,
=10×10×0.16,
=100×0.16,
=16;
(2)6.4×4.2-4.2×
,2 5
=4.2×(6.4-0.4),
=4.2×6,
=25.2;
(3)(0.3+
)×1.6-1 5
,4 5
=0.5×1.6-0.8,
=0.8-0.8,
=0;
(4)9÷[1-(
+2 5
)],9 20
=9÷[1-
],17 20
=9÷
,3 20
=60.