25%×63+37×![]() | 101× -![]() | 375-448÷8×5 |
| [75×(6.9-3.72)]÷0.6 | ( + - )×36 | +( + )÷ . |
,=0.25×63+37×0.25,
=0.25×(63+37),
=0.25×100,
=25;
(2)101×
-
,=(101-1)×
,=100×
,=80;
(3)375-448÷8×5,
=375-56×5,
=375-280,
=95;
(4)[75×(6.9-3.72)]÷0.6,
=[75×3.18]÷0.6,
=238.5÷0.6,
=397.5;
(5)(
+
-
)×36,=
×36+
×36-
×36,=16+9-15,
=25-15,
=10;
(6)
+(
+
)÷
,=
+
÷
,=
+
,=
.分析:(1)根据乘法分配律进行计算;
(2)根据乘法分配律进行计算;
(3)先算除法,再算乘法,最后算减法;
(4)先算减法,再算乘法,最后算除法;
(5)根据乘法分配律进行计算;
(6)先算小括号里面的加法,再算除法,最后算小括号外面的加法.
点评:四则运算,先弄清运算顺序,然后再进一步计算即可,能简算的要简算.