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At 10:00 AM a truck started traveling from point A with a speed of 40mph. 3 hours and 10 minutes later a car started to drive from point A in the same direction with an average speed of 60mph. At what time will the car catch up with the truck?

1 Answer

1 vote

Answer:

12:07 pm

Explanation:

The question is on relative speed

Calculate the distance covered by truck after 3hours and 10 minutes

Given; speed of truck= 40mph

Time the truck took to travel before the car started to drive from point A= 3h 10 minutes

Change hours to minutes= (60×3) + 10 = 190 minutes

Formulae for speed, S=d/t where S is speed of truck, d is distance covered and t is time

if S=d/t then distance d=S×t

d= 40×190/60 =380/3 =126.67 miles

Finding the time the car catch up with the truck

t=d/S where d=126.67 miles and speed of car = 60mph

t= 126.67/60 = 2.11 hours

Change hours to minutes

1 hr=60minutes

2.11 hrs= 2.11×60=126.67 minutes⇒2hrs and 6.67 minutes

t⇒2 hrs 7minutes

Add to the departure time

10.00 + 2: 07 = 12:07 pm