An airplane flew 3 hours with a 30 mph head wind. The return trip with a tail wind of the same speed took 2 hours. Find the speed of the plane in still air.

d = 3(r − 30) and d = 2(r + 30)

d = 3(r + 30) and d = 2(r − 30)

d = 5(r + 30)

None of these systems can be used to solve this problem

Question

An airplane flew 3 hours with a 30 mph head wind. The return trip with a tail wind of the same speed took 2 hours. Find the speed of the plane in still air.

 d = 3(r − 30) and d = 2(r + 30)

 d = 3(r + 30) and d = 2(r − 30)

 d = 5(r + 30)

 None of these systems can be used to solve this problem

anonymous · Answer

A 30 mile head wind is working against the rate of the plane.  A 30 mile tail wind is working together with the rate of the plane.  Recall that distance is equal to rate times time.  D=RT.  Substitute the given information and you should be able to answer the question.