Kellogg Test Question

Question

The subway train offers access to all twelve intersections downtown. If every intersection is .75 miles apart and the train travels at 20 mph and spends 45 seconds at every stop to unload and onboard new customers, how long will it take to get from the first intersection to the last intersection?

Answer 1

Remember that distance = rate × time.

 

 

Let's figure out the total distance of the train's trip. There are 12 intersections, but let's assume the train starts at the first and ends at the last. That means it travels the 0.75-mile separation distance 11 times along its journey. That's a total distance of 0.75(11) = 8.25 miles.

 

Since the train travels at 20 mph, we can find the time it spends in transit, t:

 

8.25 = 20t

0.4125 = t

 

The train takes 0.4125 hours to travel between stops.

 

 

However, we haven't taken into account the time it spends at each stop. It spends 45 seconds at each of the 12 stops, which is a total of:

 

45(12) = 540 seconds

540 seconds = 540/60 minutes = 9 minutes = 9/60 hours = 0.15 hours

 

That's a grand total of 0.4125 + 0.15 = 0.5625 hours.

 

 

Maybe we'd rather have an answer in minutes, so...

 

0.5625 hours = 0.5625(60) minutes = 33.75 minutes

 

 

And in seconds...

 

33.75 minutes = 33.75(60) seconds = 2025 seconds