Set X is given by {a, 2a, 3a, 4a, 5a} where ‘a’ is a positive integer. If element ‘a’ in Set X is replaced by ‘b’ and b < a, then which of the following must be true?
I.Mean would not change.
II.Median would not change.
III. Standard deviation would not change
  • a)
    I only
  • b)
    II only
  • c)
    III only
  • d)
    Both I and II
  • e)
    Both II and III
Correct answer is option 'B'. Can you explain this answer?
Related Test: Test: Statistics- 1

GMAT Question

Say a = 2 -- 2,4,6,8,10 - Mean = 6 Median = 6 .
B = 1,2,3,4,5 - Mean is 3 & Median = 3.

So the mean and median are for both sets! :/

This discussion on Set X is given by {a, 2a, 3a, 4a, 5a} where a is a positive integer. If element a in Set X is replaced by b and b a, then which of the following must be true?I.Mean would not change.II.Median would not change.III. Standard deviation would not changea)I onlyb)II onlyc)III onlyd)Both I and IIe)Both II and IIICorrect answer is option 'B'. Can you explain this answer? is done on EduRev Study Group by GMAT Students. The Questions and Answers of Set X is given by {a, 2a, 3a, 4a, 5a} where a is a positive integer. If element a in Set X is replaced by b and b a, then which of the following must be true?I.Mean would not change.II.Median would not change.III. Standard deviation would not changea)I onlyb)II onlyc)III onlyd)Both I and IIe)Both II and IIICorrect answer is option 'B'. Can you explain this answer? are solved by group of students and teacher of GMAT, which is also the largest student community of GMAT. If the answer is not available please wait for a while and a community member will probably answer this soon. You can study other questions, MCQs, videos and tests for GMAT on EduRev and even discuss your questions like Set X is given by {a, 2a, 3a, 4a, 5a} where a is a positive integer. If element a in Set X is replaced by b and b a, then which of the following must be true?I.Mean would not change.II.Median would not change.III. Standard deviation would not changea)I onlyb)II onlyc)III onlyd)Both I and IIe)Both II and IIICorrect answer is option 'B'. Can you explain this answer? over here on EduRev! Apart from being the largest GMAT community, EduRev has the largest solved Question bank for GMAT.