问题 解答题
解比例.
4:16=9:X
1
10
1
2
=X:
1
8
0.5
0.25
=
0.2
X
答案

(1)4:16=9:x,

4x=9×16,

4x÷4=9×16÷4,

x=36;

(2)

1
10
1
2
=x:
1
8

1
2
x=
1
10
×
1
8

1
2
x×2=
1
80
×2,

x=

1
40

(3)

0.5
0.25
=
0.2
X

0.5x=0.05,

0.5x÷0.5=0.05÷0.5,

x=0.1.

综合
单项选择题