(X-60)*0.4*70%+60*0.4=0.36*X

问题描述:

(X-60)*0.4*70%+60*0.4=0.36*X

(X-60)*0.4*70%+60*0.4=0.36*X
去括号,得0.28x-16.8+24=0.36x
移项合并,得 -0.08x=-7.2
系数化为1,得 x=90