Question

Two cars at the same point on I-75. One heads north going 75mph and one heads south going 60mph. How long will it take for the cars to be at 420 miles apart?

Answer 1

It will take 3 hours 6 minutes 40 seconds for the cars to be 420 miles apart.

Step-by-step explanation:

Step 1; The cars are traveling in the opposite direction at different speeds. One is going north at a speed of 75 mph while the other is going 60 mph. So for every hour, the cars are traveling they increase the distance between in between themselves by 75 miles + 60 miles = 135 miles.

Step 2; Assume that in x hours the distance between them is 420 miles. To calculate x we divide the distance to be traveled by the distance being traveled every hour.

x = distance to be covered / distance being traveled every hour

= 420 / 135 = 3.11 hours

We multiply the 0.11 hours with 60 to convert it into minutes. 0.11 × 60 = 6.66 minutes and if we do the same for seconds, 0.66 minutes × 60 = 40 seconds.