If Juan takes 11 seconds to run Y yards. How many seconds w

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If Juan takes 11 seconds to run Y yards.
How many seconds will it take him to run x yards at the same rate?

Answer:
11x/y

I understand that D = R * T
Questions
Why is the rate = y/11 and not 11 over Y since, If Juan takes 11 seconds to run Y yards.


Why is the equation
X= y/11 *t

Can someone walk me through?
These word problems are confusing?

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by Mani_mba » Sun Nov 02, 2008 7:34 pm
I think you almost got it ..
This is my approach:
------------------------
Juan takes 11 seconds to run y yards .
He would take 11/y seconds to run 1 yard.

So for x yards, he would take x(11/y).

In your approach:
---------------------
D = RT
y = (R) 11
R = y/11

For x yards:

x = (R) t
t = x/R = 11x/y.

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by earth@work » Sun Nov 02, 2008 7:43 pm
D = R * T; R=D/T
now, equation X= y/11 *t
x=(y/11)*t
x=(old distance=y)/(old time=11sec) *t
which is correct as (old distance/old time)=constant speed,R
New Distance(=x) =R*t

hope this clears ur doubt

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by raunekk » Sun Nov 02, 2008 9:51 pm
rate= distance / time

hence rate=y yards/ 11 secs

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by Jeff@TargetTestPrep » Tue Apr 21, 2015 1:23 pm
susanring wrote:If Juan takes 11 seconds to run Y yards.
How many seconds will it take him to run x yards at the same rate?

Answer:
11x/y

I understand that D = R * T
Questions
Why is the rate = y/11 and not 11 over Y since, If Juan takes 11 seconds to run Y yards.


Why is the equation
X= y/11 *t

Can someone walk me through?
These word problems are confusing?
If Juan takes 11 seconds to run y yards, how many seconds will it take him to run x yards at the same rate?

(A) 11x/y
(B) 11y/x
(C) x/(11y)
(D) 11/(xy)
(E) xy/11

Solution:

This problem is testing us on the Rate x Time = Distance relationship. This relationship also tells us that Rate = Distance/Time and Time = Distance/Rate.

Ultimately, we are looking for how many seconds it will take Juan to run x yards. Thus, the equation we'll use is: Time = Distance/Rate. We know the distance is x yards, and we need to find Juan's rate.

We can find Juan's rate as follows: Rate = Distance/Time = y yards/11 seconds

Using that rate, we need to determine how long it takes him to run x yards at the same rate. So we have:

Time = Distance/Rate

Time = x yards/(y yards/11 seconds)

Time = (x yards) x (11 seconds/y yards)

Time = 11x/y seconds

The answer is A

Jeffrey Miller
Head of GMAT Instruction
[email protected]

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by [email protected] » Tue Apr 21, 2015 8:13 pm
Hi All,

While the original post is quite old, there are a couple of lessons that can be taken from this prompt:

1) Be sure to INCLUDE the answer choices. By not including the answers, the original poster is forced (and forces us) to approach this question in one general way: with algebra. Most questions on Test Day can be approached in a variety of different ways IF you consider how the answer choices are written.

2) This question is actually perfect for TESTing VALUES. Since Jeff has included the answer choices with his post, we can properly TEST VALUES.

We're told that it takes Juan 11 seconds to run Y yards. We're asked how many seconds it takes him to run X yards at that same rate.

IF....
Y = 2
X = 4
We know that Juan takes 11 seconds to run 2 yards. At that same rate, he would need 22 seconds to run 4 yards. So we're looking for an answer that = 22 when Y = 2 and X = 4...

Answer A: 11X/Y = 44/2 = 22 This IS a match
Answer B: 11Y/X = 22/4 NOT a match
Answer C: X/(11Y) = 2/44 NOT a match
Answer D: 11/(XY) = 11/8 NOT a match
Answer E: (XY)/11 = 8/11 NOT a match

Final Answer: A

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
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