题目内容
用简便算法计算
÷7+
×
+(
+
)×
×16-
.
| 8 |
| 13 |
| 1 |
| 7 |
| 5 |
| 13 |
| 2 |
| 3 |
| 8 |
| 7 |
| 1 |
| 2 |
| 7 |
| 24 |
| 8 |
| 15 |
| 8 |
| 15 |
分析:(1)把除法改为乘法,运用乘法分配律的逆运算简算;
(2)先算括号内的,再算括号外的乘法,最后算括号外的加法;
(3)运用乘法分配律的逆运算简算.
(2)先算括号内的,再算括号外的乘法,最后算括号外的加法;
(3)运用乘法分配律的逆运算简算.
解答:解:(1)
÷7+
×
,
=
×
+
×
,
=(
+
)×
,
=1×
,
=
;
(2)
+(
+
)×
,
=
+
×
,
=
+
,
=
;
(3)
×16-
,
=
×(16-1),
=
×15,
=8.
| 8 |
| 13 |
| 1 |
| 7 |
| 5 |
| 13 |
=
| 8 |
| 13 |
| 1 |
| 7 |
| 1 |
| 7 |
| 5 |
| 13 |
=(
| 8 |
| 13 |
| 5 |
| 13 |
| 1 |
| 7 |
=1×
| 1 |
| 7 |
=
| 1 |
| 7 |
(2)
| 2 |
| 3 |
| 8 |
| 7 |
| 1 |
| 2 |
| 7 |
| 24 |
=
| 2 |
| 3 |
| 23 |
| 14 |
| 7 |
| 24 |
=
| 2 |
| 3 |
| 23 |
| 48 |
=
| 55 |
| 48 |
(3)
| 8 |
| 15 |
| 8 |
| 15 |
=
| 8 |
| 15 |
=
| 8 |
| 15 |
=8.
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