题目内容
计算下面各题,能简算的要简算.
÷
×
×99+
(
-
)÷
+
(
+
-
)×24
+
×
×2.5+
×
.
| 8 |
| 15 |
| 4 |
| 9 |
| 5 |
| 6 |
| 4 |
| 25 |
| 4 |
| 25 |
(
| 7 |
| 12 |
| 1 |
| 4 |
| 1 |
| 3 |
| 1 |
| 6 |
(
| 2 |
| 3 |
| 1 |
| 4 |
| 5 |
| 12 |
| 3 |
| 4 |
| 1 |
| 4 |
| 2 |
| 3 |
| 13 |
| 18 |
| 5 |
| 2 |
| 5 |
| 18 |
分析:(1)把除法转化为乘法,约分计算;
(2)(4)运用乘法分配律简算;
(3)先算括号内的,再算括号外的除法,最后算加法;
(5)先算乘法,再算加法;
(6)把小数化为分数,运用乘法分配律简算.
(2)(4)运用乘法分配律简算;
(3)先算括号内的,再算括号外的除法,最后算加法;
(5)先算乘法,再算加法;
(6)把小数化为分数,运用乘法分配律简算.
解答:解:(1)
÷
×
,
=
×
×
,
=1;
(2)
×99+
,
=
×(99+1),
=
×100,
=16;
(3)(
-
)÷
+
,
=
÷
+
,
=1+
,
=1
;
(4)(
+
-
)×24,
=
×24+
×24-
×24,
=16+6-10,
=12;
(5)
+
×
,
=
+
,
=
;
(6)
×2.5+
×
,
=
×
+
×
,
=(
+
)×
,
=1×
,
=
.
| 8 |
| 15 |
| 4 |
| 9 |
| 5 |
| 6 |
=
| 8 |
| 15 |
| 9 |
| 4 |
| 5 |
| 6 |
=1;
(2)
| 4 |
| 25 |
| 4 |
| 25 |
=
| 4 |
| 25 |
=
| 4 |
| 25 |
=16;
(3)(
| 7 |
| 12 |
| 1 |
| 4 |
| 1 |
| 3 |
| 1 |
| 6 |
=
| 1 |
| 3 |
| 1 |
| 3 |
| 1 |
| 6 |
=1+
| 1 |
| 6 |
=1
| 1 |
| 6 |
(4)(
| 2 |
| 3 |
| 1 |
| 4 |
| 5 |
| 12 |
=
| 2 |
| 3 |
| 1 |
| 4 |
| 5 |
| 12 |
=16+6-10,
=12;
(5)
| 3 |
| 4 |
| 1 |
| 4 |
| 2 |
| 3 |
=
| 3 |
| 4 |
| 1 |
| 6 |
=
| 11 |
| 12 |
(6)
| 13 |
| 18 |
| 5 |
| 2 |
| 5 |
| 18 |
=
| 13 |
| 18 |
| 5 |
| 2 |
| 5 |
| 2 |
| 5 |
| 18 |
=(
| 5 |
| 18 |
| 13 |
| 18 |
| 5 |
| 2 |
=1×
| 5 |
| 2 |
=
| 5 |
| 2 |
点评:此题考查了分数的四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律简便计算.
练习册系列答案
相关题目