Each week Manhattan GMAT posts a GMAT question on our blog and follows up with the answer the next day. Are you up for the challenge?
It takes n Type 1 machines six times as long to produce 120 bolts as it takes 2n Type 2 machines, with each machine running at a constant rate that is the same for all machines of a particular type. Together, one Type 1 machine and one Type 2 machine can make 24/n bolts in 4 hours. How many hours will it take for 5n Type 1 machines to produce 60 bolts?
(A) 2
(B) 4
(C) 6
(D) 8
(E) 10