Events & Promotions
|
|
GMAT Club Daily Prep
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Aug 2610:00 AM EDT
-11:59 PM EDT
Save up to $1,000 on select GMAT prep now. This Fall, achieve your most ambitious goals with millions of student success stories behind you.
Aug 2710:00 AM EDT
-11:00 AM EDT
We’ve worked incredibly hard to build TTP into the best test prep experience possible, and it would mean a lot to us to win Newsweek’s 2026 Readers’ Choice Award for Best Test Prep. If TTP has helped you, we’d be incredibly grateful for your vote.
Sep 0609:30 AM EDT
-12:30 PM EST
Top scores are possible when you enroll in a powerful EA course, taught live online + 6 months access to TTP OnDemand video courses included! Perfect class schedule and easy course access for working professionals. Class starts Sept. 6, 9:30am-12:30pm EST
Sep 0907:00 AM PDT
-10:00 AM PDT
Meet AdComs and explore top Master’s programs - MiM, MiF, MSc, MSBA and more. - Application Fee Waivers - Free 1-Week of GMAT Club Tests: - Master's Application Toolkit - Grand Prize Giveaway
Sep 1507:00 PM EDT
-09:00 PM EST
Elite scores are possible when you enroll in a powerful GMAT course, taught live online + 6 months access to TTP OnDemand video courses included! Class starts Tues/Thurs Sept. 15, 2026 - Nov. 15, 2027, 7:00pm-9:00pm EST
Sep 2108:00 PM EDT
-10:00 PM EDT
Elite scores are possible when you enroll in a powerful GMAT course, taught live online + 6 months access to TTP OnDemand video courses included! Class starts Tues/Thurs Oct. 13, 2026 - Jan. 7, 2027, 8:00pm-10:00pm EST
08 Jul 2017, 00:02
Kudos
Bookmarks
Could someone say,
1) What happens to S.D when a number is added/subtracted to all the numbers in the set?(set of consecutive integers)eg:{5,6,7,8,...}
2) What happens to S.D when a number is added/subtracted to all the numbers in the set?(set of different integers)eg{-4,9,2,-1..}
2) What happens to S.D when a number is added/subtracted to all the numbers in the set?(set of same integers) eg: {3,3,3,3,3,}
Similarly,
1) What happens to S.D when a number is multiplied/divided to all the numbers in the set?(set of consecutive integers)eg:{5,6,7,8,...}
2) What happens to S.D when a number is multiplied/divided to all the numbers in the set?(set of different integers)eg{-4,9,2,-1..}
2) What happens to S.D when a number is multiplied/divided to all the numbers in the set?(set of same integers) eg: {3,3,3,3,3,}
1) What happens to S.D when a number is added/subtracted to all the numbers in the set?(set of consecutive integers)eg:{5,6,7,8,...}
2) What happens to S.D when a number is added/subtracted to all the numbers in the set?(set of different integers)eg{-4,9,2,-1..}
2) What happens to S.D when a number is added/subtracted to all the numbers in the set?(set of same integers) eg: {3,3,3,3,3,}
Similarly,
1) What happens to S.D when a number is multiplied/divided to all the numbers in the set?(set of consecutive integers)eg:{5,6,7,8,...}
2) What happens to S.D when a number is multiplied/divided to all the numbers in the set?(set of different integers)eg{-4,9,2,-1..}
2) What happens to S.D when a number is multiplied/divided to all the numbers in the set?(set of same integers) eg: {3,3,3,3,3,}
Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
08 Jul 2017, 04:31
Kudos
Bookmarks
The answer to your first three questions is the same -- if you add a constant to every value in a list, the standard deviation will not change. It doesn't matter what the list is. So the standard deviation of these two lists, for example:
2, 7, 10, 50
and
22, 27, 30, 70
is the same, because we can make the second list by adding 20 to every value in the first list. The reason the standard deviation does not change is because standard deviation is based on the distance between your elements, and when we add 20 to everything, the distances between our values don't change at all.
When you multiply every value in a list by a constant, the standard deviation will also be multiplied by that constant. So if you multiply every value in a list by 3, the standard deviation will be multiplied by 3. The standard deviation of the second list below is 3 times the s.d. of the first:
2, 7, 10, 50
6, 21, 30, 150
Notice that when we multiply by 3, we 'stretch out' the distances between values -- the distances between consecutive values in the second list are 3 times larger than in the first list. That's why the standard deviation changes when you multiply.
If instead you divide everything in a list by 3, then you're really just multiplying everything by 1/3, and so the standard deviation will be multiplied by 1/3.
These principles apply no matter what kind of list or set you're working with.
2, 7, 10, 50
and
22, 27, 30, 70
is the same, because we can make the second list by adding 20 to every value in the first list. The reason the standard deviation does not change is because standard deviation is based on the distance between your elements, and when we add 20 to everything, the distances between our values don't change at all.
When you multiply every value in a list by a constant, the standard deviation will also be multiplied by that constant. So if you multiply every value in a list by 3, the standard deviation will be multiplied by 3. The standard deviation of the second list below is 3 times the s.d. of the first:
2, 7, 10, 50
6, 21, 30, 150
Notice that when we multiply by 3, we 'stretch out' the distances between values -- the distances between consecutive values in the second list are 3 times larger than in the first list. That's why the standard deviation changes when you multiply.
If instead you divide everything in a list by 3, then you're really just multiplying everything by 1/3, and so the standard deviation will be multiplied by 1/3.
These principles apply no matter what kind of list or set you're working with.
