Question 278371

In the jet stream the plane went 
5*(j+80)
out of the stream it went 4j


5*(j+80)-550=4j
5j+400-550=4j
j=150 mph out of jet stream.
check
5*230-550=600
1150-550=600
600=600
ok
altogether the plane flew 1150+600 =1750 miles in 9 hours.