(X-30) :(3/7X+30)=3:2等于多少
问题描述:
(X-30) :(3/7X+30)=3:2
等于多少
答
(X-30) :(3/7X+30)=3:2
3*(3/7X+30)=2*(X-30)
9/7X+90=2X-60
5X/7=150
X=150*7/5
X=210