Answer:
Step-by-step explanation:
Given that,
A pilot flew from point A to point B
Distance travelled (d)=2400miles
On return from B to A
The pilot increases his speed by 20%
The total time for the trip is 8hour 20mins= 8+20/60= 8.33hours
We want to find speed from A to B
Let the speed from A to B be V,
Then the speed from B to A is
20% increased
20/100 ×V +V
0.2V+V=1.2V
Now,
Speed is given as
Speed=distance /time
So, time =distance /speed
The time he spend from A to B is
t1=d/s
Not that the distance is constant
t1=2400/V
The time he spend from B to A is
t2=d/s
Not that the distance is constant
t2=2400/(1.2V)
t2=2000/V
Now, total time is 8.33hours
Therefore, t1+t2=total time for that trip
2400/V + 2000/V = 8.33
(2400+2000)/V= 8.33
4400/V=8.33
Cross multiply
4400=8.33V
Then, divided both side by 8.33
V=4400/8.33
V=528miles/hour
Since we represent V as the speed from Point A to B, the required speed is
V=528miles/hour