Machine A produces 100 parts twice as fast as Machine B does. Machine B produces 100 parts in 60 minutes. If each machine produces parts at a constant rate, how many parts does Machine A produce in 6 minutes?	Choices:	A) 20	B) 30	C) 40	D) 10	E) 16

Rationale: "machine b produces 100 part in 60 minutes . machine a produces 100 parts twice as fast as b , so machine a produces 100 parts in 60 / 2 = 30 minutes . now , machine a produces 100 parts in 30 minutes which is 100 / 30 = 10 / 3 parts / minute . 10 / 3 parts x a total of 6 minutes = 20 a"
Answer: A