题目内容
计算下面各题,能用简便方法的要用简便方法.
×
÷
×
+
÷8
(15-15×
)×
[
-0÷(
+
)]×
(34+
)÷17
(
+
)×
÷
.
| 4 |
| 11 |
| 1 |
| 7 |
| 4 |
| 7 |
| 11 |
| 21 |
| 1 |
| 8 |
| 10 |
| 21 |
(15-15×
| 4 |
| 5 |
| 7 |
| 24 |
[
| 4 |
| 5 |
| 1 |
| 3 |
| 2 |
| 5 |
| 5 |
| 8 |
(34+
| 34 |
| 47 |
(
| 5 |
| 6 |
| 2 |
| 9 |
| 4 |
| 5 |
| 19 |
| 20 |
分析:(1)先把除法变成乘法,再运用乘法结合律简算;
(2)(5)先把除法变成乘法,再运用乘法分配律简算;
(3)先算小括号里面的乘法,再算小括号里面的减法,最后算括号外的乘法;
(4)先根据0除以任何非0的数都得0计算中括号里面的除法,再算中括号里面的减法,最后算括号外的乘法;
(6)先算小括号里面的加法,再把除法变成乘法,运用乘法交换律简算.
(2)(5)先把除法变成乘法,再运用乘法分配律简算;
(3)先算小括号里面的乘法,再算小括号里面的减法,最后算括号外的乘法;
(4)先根据0除以任何非0的数都得0计算中括号里面的除法,再算中括号里面的减法,最后算括号外的乘法;
(6)先算小括号里面的加法,再把除法变成乘法,运用乘法交换律简算.
解答:解:(1)
×
÷
,
=
×
×
,
=
×(
×
),
=
×
,
=
;
(2)
×
+
÷8,
=
×
+
×
,
=(
+
)×
,
=1×
,
=
;
(3)(15-15×
)×
,
=(15-12)×
,
=3×
,
=
;
(4)[
-0÷(
+
)]×
,
=[
-0]×
,
=
×
,
=
;
(5)(34+
)÷17,
=(34+
)×
,
=34×
+
×
,
=2+
,
=2
;
(6)(
+
)×
÷
,
=
×
×
,
=
×
×
,
=
×
,
=
.
| 4 |
| 11 |
| 1 |
| 7 |
| 4 |
| 7 |
=
| 4 |
| 11 |
| 1 |
| 7 |
| 7 |
| 4 |
=
| 4 |
| 11 |
| 1 |
| 7 |
| 7 |
| 4 |
=
| 4 |
| 11 |
| 1 |
| 4 |
=
| 1 |
| 11 |
(2)
| 11 |
| 21 |
| 1 |
| 8 |
| 10 |
| 21 |
=
| 11 |
| 21 |
| 1 |
| 8 |
| 10 |
| 21 |
| 1 |
| 8 |
=(
| 11 |
| 21 |
| 10 |
| 21 |
| 1 |
| 8 |
=1×
| 1 |
| 8 |
=
| 1 |
| 8 |
(3)(15-15×
| 4 |
| 5 |
| 7 |
| 24 |
=(15-12)×
| 7 |
| 24 |
=3×
| 7 |
| 24 |
=
| 7 |
| 8 |
(4)[
| 4 |
| 5 |
| 1 |
| 3 |
| 2 |
| 5 |
| 5 |
| 8 |
=[
| 4 |
| 5 |
| 5 |
| 8 |
=
| 4 |
| 5 |
| 5 |
| 8 |
=
| 1 |
| 2 |
(5)(34+
| 34 |
| 47 |
=(34+
| 34 |
| 47 |
| 1 |
| 17 |
=34×
| 1 |
| 17 |
| 34 |
| 47 |
| 1 |
| 17 |
=2+
| 2 |
| 47 |
=2
| 2 |
| 47 |
(6)(
| 5 |
| 6 |
| 2 |
| 9 |
| 4 |
| 5 |
| 19 |
| 20 |
=
| 19 |
| 18 |
| 4 |
| 5 |
| 20 |
| 19 |
=
| 19 |
| 18 |
| 20 |
| 19 |
| 4 |
| 5 |
=
| 10 |
| 9 |
| 4 |
| 5 |
=
| 8 |
| 9 |
点评:完成本题要注意分析式中数据,运用合适的简便方法计算.
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