解方程. 6:22/3=x:4 x:10/7=0.3:12 7×(13-x)=3x.
问题描述:
解方程.
6:2
=x:4 2 3
x:
=0.3:12 10 7
7×(13-x)=3x.
答
(1)6:2
=x:42 3
2
x=6×42 3
2
x÷22 3
=24÷22 3
2 3
x=9;
(2)x:
=0.3:1210 7
12x=
×0.310 7
12x÷12=
÷123 7
x=
;1 28
(3)7×(13-x)=3x
91-7x=3x
91-7x+7x=3x+7x
91÷10=10x÷10
x=9.1.