Sara leaves home at 8 am and drives at an average speed of 50 miles per hour. Her husband leaves 2 minutes later at 60 mph, what time will he catch up

Question

What time will he catch up

Answer 1

50 miles per hour x 1 hour / 60 minutes = 5/6 miles per minute

 

60 miles per hour x 1 hour/60 minutes = 1 mile per minute

 

distance = rate x time

 

D = R * T = (5/6)t   <----- Sara, where time t is in minutes

 

D = R * t = 1*(t-2) <---- Husband, where time t is in minutes; 2 minutes less, 1 mile per minute

 

The distances are the same.

 

(5/6)t = t - 2

 

0 = t - 2 - (5/6)t

 

0 = (1/6)t - 2

 

2 = (1/6)t

 

t = 12

 

Sara drives 12 minutes, for a distance of 5/6*12 = 10 miles

 

Husband drives for 10 minutes which at 1 mile per minute is 10 miles.

 

They will meet at 8:12 am