Problema Solution
A plane had been flying for 40 minutes when a change of wind direction doubled its ground speed. The entire trip of 160 miles took 2 hours. How far did the plane travel during the first 40 minutes?
Answer provided by our tutors
let 'v' represent the initial velocity, then '2v' represents the final velocity
distance = velocity * time
40/60 is time represented in hours
the distance flown before the wind change:
(40/60)v
the distance flown after the wind change (velocity of 2v, time 40:
(2 - (40/60))(2v)
the total distance is then represented by:
160 = (40/60)v + (2-(40/60))(2v)
solving for 'v' we have:
v=48
The plane flew 40 minutes at 48 mph, so the distance was:
48 miles/hour * (40/60) hours = 32 miles
The plane flew 32 miles before the speed doubled