A certain automobile company’s best-selling model is the Speedster. The Speedster, like all of their other models, comes in coupe and convertible styles. 3/4 of the current inventory is Speedsters, of which 3/5 are convertibles. If there are 30 vehicles that are not Speedsters, how many Speedster convertibles are there? Choose the most appropriate option:	A) 30	B) 54	C) 60	D) 70	E) 90

Rationale: "total vehicle = 3 / 4 of speedster + 1 / 4 of others . speedster convertibles = 3 / 4 total vehicle * 3 / 5 given : 1 / 4 constitutes 30 vehicles . hence 3 / 4 constitutes 90 speedster convertibls = 90 * 3 / 5 = 54 b"
Answer: B