Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Robots X, Y, and Z each assemble components at their [#permalink]
31 Mar 2009, 16:00

00:00

A

B

C

D

E

Difficulty:

25% (low)

Question Stats:

70% (02:04) correct
30% (01:08) wrong based on 90 sessions

Robots X, Y, and Z each assemble components at their respective constant rates. If r_x is the ratio of Robot X's constant rate to Robot Z's constant rate and r_y is the ratio of Robot Y's constant rate to Robot Z's constant rate, is Robot Z's constant rate the greatest of the three?

Re: DS - Rate problem / Ration problem??? - OG 12 [#permalink]
01 Apr 2009, 01:27

I think E Lets take V as Robot Z's constant rate

is Robot Z's constant rate the greatest of the three?

X:Y:Z=Va:Vb:V now to have V highest we need to know whether V is <0 or >0 V could be 2 or say, 1/2 it changes the whole picture

Robots X, Y, and Z each assemble components in their respective constant rates. If a is the ration of Robot X's constant rate to Robot Z's constant rate and b is the ratio of Robot Y's constant rate to Robot Z's constant rate, is Robot Z's constant rate the greatest of the three. 1) a < b 2) b < 1
_________________

Re: Robots X, Y, and Z each assemble [#permalink]
03 Jan 2011, 20:26

We need both the information if the constant rate for Z is greater or not. 1. says that constant rate of Y is greater than X. x/z < x/y 2. says that constant rate of Y is smaller than Z. y/z <1

Re: Robots X, Y, and Z each assemble [#permalink]
04 Jan 2011, 02:33

1

This post received KUDOS

Expert's post

ajit257 wrote:

see attachment

Can some explain the reasoning behind this ques.

Robots X, Y, and Z each assemble components at their respective constant rates. If rx is the ratio of robot X's constant rate to robot Z's constant rate and ry is the ratio of robot Y's constant rate to robot Z's constant rate, is robot Z's constant rate the greatest of the three?

Let the rates of robots X, Y, and Z be x, y, and z respectively. Given: r_x=\frac{x}{z} and r_y=\frac{y}{z}. Question is z>x and z>y?

(1) r_x<r_y --> \frac{x}{z}<\frac{y}{z} --> x<y. Not sufficient.

(2) r_y<1 --> \frac{y}{z}<1 --> y<z. Not sufficient.