Given, Alan leaves Los Angeles at 8:00 am to San Fransisco which is 400 miles away from Los Angeles.
He travels at a rate of 50 mph.
So 50 miles distance covered in 1 hour
1 mile distance covered in hour
400 miles distance covered in hours = 8 hours.
Alan takes 8 hours to reach San Fransisco.
The time will be = 8:00 am + 8 hours = 4:00 pm.
Now Beth leaves Los Angeles at 9:00 am.
His speed is 60mph.
So 400 miles distance covered in hours.
We can simplify by dividing 400 and 60 both by 20. We will get there after simplification.
So Beth takes hours to reach San Fransisco.
Let's convert hours to minute. We know that there are 60 minutes in 1 hour.
So hours = minutes
= minutes = minutes
= minutes = minutes = 6 hours 40 minutes.
So Beth takes 6 hours and 40 minutes to reach San Fransisco.
The time will be = 9:00 am + 6 hours 40 minutes = 3:40 pm.
So we have got Beth gets to San Fransisco first.
He will wait for = 20 minutes.
We have got the required answer here.