问题
解答题
下面各题,怎样算简便就怎样算. 3.7×
38×
9.9+99.9+999.9 6.8÷4-1.2×25%+4
(
|
答案
(1)3.7×
+5.3×0.75+3 4 3 4
=0.75×(3.7+5.3+1)
=7.5;
(2)38×3 37
=(37+1)×3 37
=3+3 37
=3
;3 37
(3)9.9+99.9+999.9
=10+100+1000-0.1-0.1-0.1
=1110-0.3
=1109.7;
(4)6.8÷4-1.2×25%+4
×0.252 5
=6.8×0.25-1.2×0.25+4.4×0.25
=(6.8-1.2+4.4)×0.25
=10×0.25
=2.5;
(5)(
+5 12
)×24×151 15
=
×24×15+5 12
×24×151 15
=150+24
=174.