Answer:
807mph is the rate of the jet, and 75mph is the jetstream.
Step-by-step explanation:
We need to start from the formula of speed: V=d/t
We have two travels, with and against the jetstream, both done in the same time (9hr). We can arrange a equation sytem with this information;
V - X = 6588miles/9hr (against the jetstream, X).
V + X = 7938miles/9hr (with the jetstream, X).
Clear V from the 1st equation:
V = (6588/9) + X
V = 732 + X
Now, replace it into the 2nd equation:
(732+X) + X = 7938/9
2X + 732 = 882
2X = 882 - 732
X = 150/2
X = 75mph is the jetstream.
Now we have, the jetstream, replace it into any of the equation to find V:
V - 75mph = 6588mi/9h
V = 732mph + 75mph
V = 807mph is the rate of the jet.
