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

Redeem

positive integers

Expert replies
Source: — Problem Solving |

by ajith » Sat Feb 20, 2010 4:00 am
gmatnmein2010 wrote:Given distinct positive integers 1, 11, 3, x, 2, and 9, which of the following could be the median?


1)3


2)5


3)7


4)8


5)9
1,2,3,x,9,11 is a possibility when 4<x<9

and then the median = (x+3)/2

When x = 7; the median could be (7+3)/2 = 5
Hence C
Always borrow money from a pessimist, he doesn't expect to be paid back.
Join the discussion

by shashank.ism » Sat Feb 20, 2010 9:11 am
ajith wrote:
gmatnmein2010 wrote:Given distinct positive integers 1, 11, 3, x, 2, and 9, which of the following could be the median?
1)3
2)5
3)7
4)8
5)9
1,2,3,x,9,11 is a possibility when 4<x<9

and then the median = (x+3)/2

When x = 7; the median could be (7+3)/2 = 5
Hence C
we try to arrange the numbers n sequence 1,2,3,9,11
if 4<= x<=8 median = 3.5,4,4.5,5,5.5
if x=10 median = [9+3]/2 =6
if x>11 median = [9+3]/2 =6

[spoiler]so Ans(2) ie 5[/spoiler]
My Websites:
www.mba.webmaggu.com - India's social Network for MBA Aspirants

www.deal.webmaggu.com -India's online discount, coupon, free stuff informer.

www.dictionary.webmaggu.com - A compact free online dictionary with images.

Nothing is Impossible, even Impossible says I'm possible.
Join the discussion

by GMATinsight » Tue Nov 22, 2016 11:33 pm
gmatnmein2010 wrote:Given distinct positive integers 1, 11, 3, x, 2, and 9, which of the following could be the median?


1)3


2)5


3)7


4)8


5)9

Arranging in increasing order

1, 2, 3, 9, 11 and x has to come somewhere in the sets of numbers

If x<2, then Median = Average of 2 and 3 = 2.5
If x>9, then Median = Average of 3 and 9 = 6

So median must lie between 2.5 and 6

But since numbers are distinct so median can never be 3 (for median to be 3 x should be 3 as well which is not acceptable due to terms being distinct)

Hence Answer: Option B
"GMATinsight"Bhoopendra Singh & Sushma Jha
Most Comprehensive and Affordable Video Course 2000+ CONCEPT Videos and Video Solutions
Whatsapp/Mobile: +91-9999687183 l [email protected]
Contact for One-on-One FREE ONLINE DEMO Class Call/e-mail
Most Efficient and affordable One-On-One Private tutoring fee - US$40-50 per hour
Join the discussion

by Matt@VeritasPrep » Fri Nov 25, 2016 3:15 am
Arrange the five that you know first:

1, 2, 3, 9, 11

Since x is a positive integer, it must be > 0. It must be distinct from the other integers in the set, so it must be > 3.

From here, it's easiest just to try x's. If x = 4, the median = (3+4)/2 = 3.5. If x = 5, the median = (3+5)/2 = 4. If x = 6, we get another decimal. If x = 7, we get 5, so that's our median: 5.
Join the discussion

by Scott@TargetTestPrep » Sun Nov 27, 2016 5:48 pm
gmatnmein2010 wrote:Given distinct positive integers 1, 11, 3, x, 2, and 9, which of the following could be the median?


A)3
B)5
C)7
D)8
E)9
Since the integers are positive and distinct, x must be greater than 3. However, since we don't know the exact value of x, we can start by ordering the given integers from least to greatest in the following possible scenarios:

Scenario 1: If the ordering is 1, 2, 3, x, 9, 11, then x is between 3 and 9

Scenario 2: If the ordering is 1, 2, 3, 9, x, 11, then x must be 10.

Scenario 3: If the ordering is 1, 2, 3, 9, 11, x, then x is greater than 11.

In the first scenario, the median is (3 + x)/2. In the latter two scenarios, the median is (3 + 9)/2 = 6. Since 6 is not an answer choice, the median must be (x + 3)/2 in which x is an integer between 3 and 9. Because x is an integer between 3 and 9, the median, (x + 3)/2, must be some value between 3 and 6. Thus:

3 < x < 9

6 < x + 3 < 12

3 < (x + 3)/2 < 6

The only number in the choices that satisfies this condition is 5, which is answer choice B.

Answer:B

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage
Join the discussion