解方程: x-4/9x=10/21 x:4/7=5/8:11/12 6.4Χ=0.12:1.5.
问题描述:
解方程:
x-
x=4 9
10 21
x:
=4 7
:5 8
11 12
=0.12:1.5. 6.4 Χ
答
(1)x-
x=4 9
,10 21
(1-
)x=4 9
,10 21
x÷5 9
=5 9
÷10 21
,5 9
x=
;6 7
(2)x:
=4 7
:5 8
,11 12
x=11 12
×4 7
,5 8
x÷11 12
=11 12
÷5 14
,11 12
x=
;30 77
(3)
=0.12:1.5,6.4 Χ
0.12x=6.4×1.5,
0.12x=9.6,
0.12x÷0.12=9.6÷0.12,
x=80.