(2)
×2÷
×2=(3)1.25×3.2×8
+0.75=(4)(
+
)×
=(5)10÷10%=
(6)8×
-
=解:(1)0.9+99×0.9=(99+1)×0.9
=100×0.9
=90;
(2)
×2÷
×2=
×2×3×2=(
×3)×2×2=1×4
=4;
(3)1.25×3.2×8
+0.75=
×
×
+
=
+
=
;(4)(
+
)×
=
×
+
×
=
+
=
;(5)10÷10%,
=10÷0.1
=100;
(6)8×
-
=
×(8-1)=
×7=5.
分析:(1)(4)(6)运用乘法分配律简算;
(2)把除法改为乘法,运用乘法交换律与结合律简算;
(3)把小数化为分数计算;
(5)把百分数化为小数计算.
点评:此题考查了四则混合运算,注意数字转化,灵活运用所学的运算律简便计算.