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.

(1) alone: since total cost = L + M, this means that L + M = 3M, or L = 2M. so, rephrased, statement 1 says that labor cost twice as much as materials. still, this is insufficient, as picking values will show: if M = $1 and L = $2, the answer is yes, but if M = $150,000 and L = $300,000, the answer is no.
(2) alone: great, but no information at all about materials. so, if L = M = $1, then yes; if L = $1 and M = $499,997 (so that profit = $2), then no. insufficient
together: we have P '>' L which, using the rephrasing found above, rephrases to P '>' 2M also, P = 500,000 - 3M (because total cost = 3M) so

500,000 - 3M '>' 2M

500,000 '>' 5M

100,000 '>' M

since M is less than 100,000, it follows that profit, which is 500,000 - 3M, must be more than 500,000 - 3(100,000) = 200,000. answer = yes sufficient
Ans : C