Car Z travels at speed z miles per hour, and Car Y travels at speed y

Question

Car Z travels at speed z miles per hour, and Car Y travels at speed y miles per hour, and z > y. On one day, the two cars are parked at mile zero on a straight road, and they begin moving at the same time in the same direction. After 2 hours 30 minutes, the distance between the cars is 25 miles. On another day, the cars are parked 25 miles apart on the same road, and they begin moving at the same time toward each other. In 30 minutes, the cars pass each other.

Select the cars' speeds y and z such that they are jointly compatible with the given information. Make only two selections, one in each column.

Select the cars' speeds y and z such that they are jointly compatible with the given information. Make only two selections, one in each column.

poojaarora1818 · Answer

In the first scenario, cars Z & Y start at zero miles and move in the same direction. We also know that the speed of car Z is z miles per hour which is greater than car Y which is y miles per hour. So, we have the equation difference between the distances of both which is 2.5z - 2.5y = 25 We have z - y = 10 ---> eq 1, And from the second scenario we know that both cars are moving towards each other. So, the sum of their distances is 0.5z + 0.5y = 25 and z + y = 50 ---> Eq 2

By adding both equations we have z - y = 10
 z + y = 50
 z = 30
If we know z is 30 so, we put the value of z in one of the above equations and we have y as 20

Hence, z = 30 and y = 20

Oppenheimer1945 · Answer

(z-y)(2.5)=25

(z+y)(0.5)=25

=> z=30, y=20

Bismuth83 · Answer

1. The question asks us to  find the speeds of the two cars - z and y .

2.  On one day, the two cars are parked at mile zero on a straight road, and they begin moving at the same time in the same direction. After 2 hours 30 minutes, the distance between the cars is 25 miles.  Time multiplied by velocity is distance and we know the difference between the traveled distances of the 2 cars. So, we can put together an equation:  2.5 * z - 2.5 * y = 25 = 2.5(z - y) \rightarrow z - y = 10 .

3.  On another day, the cars are parked 25 miles apart on the same road, and they begin moving at the same time toward each other. In 30 minutes, the cars pass each other.  Here we can change the problem into a car with a speed z + y traveling 25 miles in 30 minutes. Now, let's put together an equation:  z + y = \frac{25}{0.5} = 50 .

4. There are two equations:  z - y = 10  and  z + y = 50 . Summing them together gives us  2z = 60 \rightarrow z = 30  and then  y = 50 - 30 = 20 .

5. Our answer will be:   y = 20 and z = 30  .

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Car Z travels at speed z miles per hour, and Car Y travels at speed y

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GMAT Two-part Analysis (TPA) Questions

Car Z travels at speed z miles per hour, and Car Y travels at speed y

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