Aplane flew 1000 miles away from london for one flight for the next flight it flew 500 miles towards london how far was the plane from london after the second flight

First flight distance traveled away from initial point (London) = 1000 miles
Second flight distance traveled towards initial point (London) = 500 miles

Distance from initial point = 1000 - 500 = 500 miles away from London after the second flight.