题目内容
脱式计算(能简算的要简算)
①
×54+54×
②
×
+
÷
③[2-(1+
)]÷
④(
-
)÷
+
.
①
| 5 |
| 27 |
| 22 |
| 27 |
②
| 2 |
| 5 |
| 4 |
| 7 |
| 3 |
| 7 |
| 5 |
| 2 |
③[2-(1+
| 2 |
| 3 |
| 2 |
| 7 |
④(
| 5 |
| 6 |
| 3 |
| 4 |
| 7 |
| 48 |
| 12 |
| 7 |
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先算加法,再算减法,最后算除法;
④先算减法,再算除法,最后算加法.
②根据乘法分配律进行计算;
③先算加法,再算减法,最后算除法;
④先算减法,再算除法,最后算加法.
解答:解:
①
×54+54×
,
=(
+
)×54,
=54;
②
×
+
÷
,
=
×
+
×
,
=
×(
+
),
=
;
③[2-(1+
)]÷
,
=[2-1
]÷
,
=
÷
,
=
;
④(
-
)÷
+
,
=
÷
+
,
=
+
,
=
.
①
| 5 |
| 27 |
| 22 |
| 27 |
=(
| 5 |
| 27 |
| 22 |
| 27 |
=54;
②
| 2 |
| 5 |
| 4 |
| 7 |
| 3 |
| 7 |
| 5 |
| 2 |
=
| 2 |
| 5 |
| 4 |
| 7 |
| 3 |
| 7 |
| 2 |
| 5 |
=
| 2 |
| 5 |
| 4 |
| 7 |
| 3 |
| 7 |
=
| 2 |
| 5 |
③[2-(1+
| 2 |
| 3 |
| 2 |
| 7 |
=[2-1
| 2 |
| 3 |
| 2 |
| 7 |
=
| 1 |
| 3 |
| 2 |
| 7 |
=
| 7 |
| 6 |
④(
| 5 |
| 6 |
| 3 |
| 4 |
| 7 |
| 48 |
| 12 |
| 7 |
=
| 1 |
| 12 |
| 7 |
| 48 |
| 12 |
| 7 |
=
| 4 |
| 7 |
| 12 |
| 7 |
=
| 16 |
| 7 |
点评:此题主要考查分数的四则混合运算的运算顺序和应用运算定律进行简便计算.
练习册系列答案
相关题目