| 10×10.7-10÷62.5% | 99%×99+99% | 4×8×1.25×25% | ( + )×23+ . |
=107-10÷0.625,
=107-16,
=91;
(2)99%×99+99%,
=99%×(99+1),
=0.99×100,
=99;
(3)4×8×1.25×25%,
=4×25%×(8×1.25),
=4×0.25×10,
=1×10,
=10;
(4)(
+
)×23+
,=
×23+
×23+
,=
+(
+
),=
+1,=1
.分析:(1)先算乘除,再算减法;
(2)运用乘法分配律简算;
(3)运用乘法交换律与结合律简算;
(4)运用乘法分配律以及加法结合律简算.
点评:此题考查了小数、分数的四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算律简便计算.