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:

I am not pretty sure but i think it is C)
A and B by itself are both insufficient. The third value is missing.
From both A) X=5+Y and B) X=10+Z and 5+Y=10+Z then Y=5+Z and from B) X=10+Z, then the values are Z, 5+Z, 10+Z and the deviation is 5 as it is in the stem.

Statement 1 says , x - y = 5.
But we dont know about z to decide.

Statement 2 says x-z = 10.
But we dont know position of y.

But combing these two,
we know that the numbers come in the order x y z with a difference of 5 each. SD = 5 . [We do not need value of y. We just want to know the difference between other nos and y. ]

Agree with BG.
Think it's C.
Try to pick up numbers
let's say y=15 then x=5+y=15+5=20 and z=x-10=10. So we have 10 15 20 and deviation is the same...moreover in general case as BG has shown we have numbers like Z,Z+5,Z+10 and we know that D(x)=sqrt((X-avg(X,Y,Z))^2+(Y-avg(X,Y,Z))^2+(Z-avg(X,Y,Z))^2)/(n-1) so we can see that the difference in bracket would be always the same if the number follow the pattern Z,Z+5,Z+10....

I am not pretty sure but i think it is C) A and B by itself are both insufficient. The third value is missing. From both A) X=5+Y and B) X=10+Z and 5+Y=10+Z then Y=5+Z and from B) X=10+Z, then the values are Z, 5+Z, 10+Z and the deviation is 5 as it is in the stem.

Great explanation! I guess I fell for the trap.

OA pls? _________________

Don't be afraid to take a flying leap of faith.. If you risk nothing, than you gain nothing...

I am not pretty sure but i think it is C) A and B by itself are both insufficient. The third value is missing. From both A) X=5+Y and B) X=10+Z and 5+Y=10+Z then Y=5+Z and from B) X=10+Z, then the values are Z, 5+Z, 10+Z and the deviation is 5 as it is in the stem.

Great explanation! I guess I fell for the trap. OA pls?

sorry guys i forget to apply range concept. if the range of a given number of observations is equal with the same no of observations, the SDs of these observations are equal and its toooooo late to apply this concept.

i misjudged that SD is higher with higher values....

It’s been a long time, since I posted. A busy schedule at office and the GMAT preparation, fully tied up with all my free hours. Anyways, now I’m back...

Ah yes. Funemployment. The time between when you quit your job and when you start your MBA. The promised land that many MBA applicants seek. The break that every...

It is that time of year again – time for Clear Admit’s annual Best of Blogging voting. Dating way back to the 2004-2005 application season, the Best of Blogging...