a twinengined air craft can fly 1200 miles from city a to ci

a twin-engined air craft can fly 1200 miles from city a to city b in 5 hours with the wind and make the return trip in 8 hours against the wind. What is the speed of the wind?
be sure to define unknowns, set up a system of equations to solve and answer the question being asked.

Solution

Equations:
p + w = 240 mph
p - w = 150
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Add the two equations and solve for \"p\":
2p = 390
p = 195 mph (speed of the plane in still air)
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Substitute into p+w=240 to solve for \"w\";
195 + w = 240
w = 45 mph (speed of the wind)