BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

GMAT Prep1 DS Question

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 19
Joined: Wed Jun 23, 2010 10:28 pm

GMAT Prep1 DS Question

by pushkin1982 » Sat Aug 21, 2010 10:17 am
4) Machines X & Y can produce components at their respective rates. How many more hours does Y take than X to produce a certain number of components?

A) X & Y working together take 2/3 of the time taken by X.
B) Y working alone takes Twice the time taken by X.
Top
Source: — Data Sufficiency |
Master | Next Rank: 500 Posts
Posts: 161
Joined: Mon Apr 05, 2010 9:06 am
Location: Mumbai
Thanked: 37 times

by 4GMAT_Mumbai » Sat Aug 21, 2010 10:24 am
Hi,

Statement 1:

Let X take 30 hours to complete the job.

1/30 + 1/Y = 1/20

1/Y = 1/20 - 1/30

1/Y = 1/60

In this case, Y takes 60 hours to complete the job.

Thus, if Y takes twice the times that X takes, then working together, they will complete the work in 2/3rd of the time taken by X alone.

How many more hours does Y take than X (in absolute terms) ? cannot tell - insufficient

Statement 2: Just a restatement of what has been implied by statement 1 - insufficient.

Combining 1 & 2: Does not take us much further.

Guess, it is E.

Hope this helps. Thanks.
Naveenan Ramachandran
4GMAT, Dadar(W) & Ghatkopar(W), Mumbai
Top
Post new topic Post Reply
• Page 1 of 1