Two trains, X and Y, started simultaneously from opposite ends of a 100-mile route and traveled toward each other on parallel tracks. Train X, traveling at a constant rate, completed the 100-mile trip in 5 hours; Train Y, traveling at a constant rate, completed the 100-mile trip in 3 hours. How many miles had Train X traveled when it met Train Y? (A) 37.5
(B) 40.0
(C) 60.0
(D) 62.5
(E) 77.5

(A) 37.5 miles

Step-by-step explanation:

The trains x and y are travelling on tracks starting simultaneously from a from opposite ends of 100 miles roads.

Translate these information into a simple represention to visualize the problem. (Picture below)

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First let's calculate the velocity of both trains.

The velocity formula is:

● V = d/t

d is the distance travelled and t is the tile needed to do it.

● V(x) = 100/5 = 20 miles per hour

● V(y) = 100/3 = 33.33.. wich is approximatively 33 after rounding to the nearest unit.

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After calculateingboth velocities, Let's find when the trains meet.

First understand what does it mean matematically when both trains meet.

Go back to the representation and notice what happens when the trains meet.

Let t be that moment.

When x and y reches the meeting point at t, the sum of the distances they have travelled is equal to the total distance wich is 100 miles .

We khow that V = d/t so d = V×t

Let's find the expression of the distances both trains travelled when they have met each other.

● d = V(x) × t

● d' = V(y) × t

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So the equation will be:

● V(x) × t + V(y) × t = 100

Factor using t

● t (V(x) + V(y) ) = 100

Replace V(x) and V(y) by their values

● t (20+33) = 100

● 53 t = 100

Divide both sides by 53

● 53t /53 = 100/53

● t = 1.88

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Replace t in the expression of the distance that train x has travelled when meeting y.

● d = V(x) × t

● d = 20 × 1.88

● d = 37.6 wich is approximatively 37.5 miles

89

step-by-step explanation: