条件A是不是有错误啊?
按照字面意思，X=A+B=1.2A=1.1B 没有解的。
3、to bid a project, the cost includes material cost and labor cost, ask the percentage of X's bid cost to Y's bid cost?
a.X's costs are 20% higher than labor costs and 10% higher than material costs.
b. Of total costs', Y'S 60% are labor costs.
(今天让我最头疼的一道题，和去年2月的73th JJ不同， 犹豫半天，选了个E）
11、to bid a project, the cost includes material cost and labor
cost, ask the percentage of X's bid cost to Y's bid cost?
a.X's costs are 20% higher than labor costs and 10% higher than
material costs.
b. Of total costs', Y'S 60% are labor costs.
这是昨天的jj，我也选了E。 | 
