A construction company was paid a total of $500,000 for a construction project. The company's only costs for the project were for labor and materials. Was the company's profit for the project greater than $150,000 ?
(1) The company's total cost was three times its cost for materials.
(2) The company's profit was greater than its cost for labor.
思路如下 500000-L-M>150000?
(1) L+M=3M
L=2M insufficient
(2)500000-3M>L insufficient
以(1)條件代入
500000>5M
M<100000
therefore, profit>15000
Ans:C
不好意思! 在打題目的過程中 突然知道怎樣解題
