(x-120)/7分之6倍x=10分之9怎样解?
问题描述:
(x-120)/7分之6倍x=10分之9怎样解?
答
(x-120)/6x/7=9/10
6x/7×(x-120)/6x/7=9/10×6x/7
(x-120)=54x/70
70(x-120)=54x
70x-8400=54x
124x=8400
x=2100/31