Answer:
3.5 hours
Step-by-step explanation:
It is given that,
Velocity of first car, v = 20 mph
Velocity of second car, v' = 60 mph
They are moving in opposite direction. Their relative speed is given by :
V = 20 mph + 60 mph = 80 mph
Distance, d = 280 miles
So,
[tex]t=\dfrac{d}{V}\\\\t=\dfrac{280}{80}\ h\\\\t=3.5\ h[/tex]
Hene, they will be 280 mile apart in 3.5 hours.
