I call this a shrinking gap question.

Currently, Train A is 15 miles ahead of Train B.
So, the GAP = 15 miles

Train A is traveling at 40 miles per hour and Train B is traveling on a parallel track in the same direction at 60 miles per hour.
Speed difference = 60 mph - 40 mph = 20 miles per hour
So, the GAP shrinks at a rate of 20 miles per hour

How many minutes will it take Train B to catch up with Train A?
In others how long will it take the GAP to decrease from 15 miles to 0 miles.

Time = distance/rate
= (15 miles)/(20 miles per hour)
= 3/4 HOURS
= 45 minutes

Answer:

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We are given that train Train A is traveling at 40 miles per hour and Train B is traveling on a parallel track in the same direction at 60 miles per hour. We need to determine how many minutes it will take Train B to catch Train A, since Train B must travel 15 more miles than Train A. Since both trains are traveling for the same amount of time, we can let each time = t hours.

Thus, Train A’s distance is 40t and Train B’s distance is 60t.

Since Train B travels 15 more miles than Train A:

40t + 15 = 60t

15 = 20t

15/20 = 3/4 = t

3/4 hour = 45 minutes

Answer: A
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\(\frac{15}{(60-40)}*60\) = 45 Minutes...

Answer must be (A) 45
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Abhishek....

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Train A is traveling at 40 miles per hour and Train B is traveling on a parallel track in the same direction at 60 miles per hour. Currently, Train A is 15 miles ahead of Train B. How many minutes will it take Train B to catch up with Train A?

Speed (Train A) = \(40 \frac{Miles}{Hour}\)

Speed (Train B) = \(60 \frac{Miles}{Hour}\)

Distance Between Train A and Train B = 15 Miles

As both Train A and Train B are moving in the same direction, we have to subtract the higher speed from the lower speed to get the relative speed

= \(60 \frac{Miles}{Hour}\) - \(40 \frac{Miles}{Hour}\) = \(20 \frac{Miles}{Hour}\)

So, lets calculate the time required for Train B to catch-up with Train A:

\(Time = \frac{Distance}{Speed}\)

\(= \frac{15}{20}\)

= 0.75 Hrs

As the time asked in the question is in minutes we will multiply it by 60

\(= 0.75 * 60\)

\(= 45 Min\)


Hence, the Answer is A
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