×0.25+ ÷4-![]() | ×0.375- ÷![]() |
- ÷ -![]() | 302×15-6950÷50. |
(1)
×0.25+
÷4-
,=
×
+
×
-
,=(
+
-1)×
,=0×
,=0;
(2)
×0.375-
÷
,=
×0.375-
×0.375,=(
-
)×0.375,=1×0.375,
=0.375;
(3)
-
÷
-
,=
-
-
,=
-(
+
),=
-1,=
;(4)302×15-6950÷50,
=4530-139,
=4391.
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,再根据连减的性质进行计算;
(4)先算乘法和除法,再算减法.
点评:四则运算,先弄清运算顺序,然后再进一步计算,能简算的要简算.