2 people 400 miles apart

They both leave at the same time
One drives 50 mph
The other drives 100 mph
How long till they meet?

1 answer

50 + 100 = 150 m/h combined speed
150 t = 400
t = 40/15 = 8/3 = 2 2/3 hr
= 2 hours and 40 minutes