问题 解答题
脱式计算(③④⑤小题用简便方法).
①635+9030÷86×13
②4.1-2.56÷(0.18+0.62)③45×101
④5.7-(1.9-1.3)
98
99
+
98
99
×98
4
5
÷〔
5
8
×(
1
6
+
1
3
)〕
答案

①635+9030÷86×13,

=635+105×13,

=635+1365,

=2000;

②4.1-2.56÷(0.18+0.62),

=4.1-2.56÷0.8,

=4.1-3.2,

=0.9;

③45×101,

=45×(100+1),

=4500+45,

=4545;

④5.7-(1.9-1.3),

=5.7-1.9+1.3,

=5.7+1.3-1.9,

=7-1.9,

=5.1;

98
99
+
98
99
×98,

=

98
99
×(1+98),

=

98
99
×99,

=98;

4
5
÷〔
5
8
×(
1
6
+
1
3
)〕,

=

4
5
÷[
5
8
×(
1
6
+
2
6
)],

=

4
5
÷[
5
8
×
1
2
],

=

4
5
÷
5
16

=

4
5
×
16
5

=

64
25

=2

14
25

问答题 简答题
问答题 简答题