Mean & Median

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Mean & Median

by Vemuri » Thu Mar 19, 2009 5:33 am
If 2 sets of numbers P & Q have the same number of elements, is the mean of set Q lower than the mean of set P?

1. Set Q consists of consecutive even integers and set P consists of consecutive odd integers.

2. The median of set Q is higher than the mean of set P.
Source: — Data Sufficiency |

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by scoobydooby » Thu Mar 19, 2009 5:40 am
1) let Q=(200,202,204) and P=(1,3,5)
=>mean of Q(202)>mean of P(3) (for evenly spaced integers mean=median)

if Q=(2,4,6) and P=(101, 103,105)
mean of Q(4)<mean of P(103)
not suff


2) median of set Q is higher than the mean of set P
=>mean of Q>mean of P (for evenly spaced integers mean=median)
sufficent

hence B

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by avenus » Thu Mar 19, 2009 9:11 am
2) median of set Q is higher than the mean of set P
=>mean of Q>mean of P (for evenly spaced integers mean=median)
sufficent

hence B
you're using info from statement 1) in the analysis of statement 2)

Answer is C)

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by Morgoth » Thu Mar 19, 2009 12:10 pm
avenus wrote:
2) median of set Q is higher than the mean of set P
=>mean of Q>mean of P (for evenly spaced integers mean=median)
sufficent

hence B
you're using info from statement 1) in the analysis of statement 2)

Answer is C)

You are correct, answer should be C.
Last edited by Morgoth on Thu Mar 19, 2009 1:13 pm, edited 1 time in total.

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Re: Mean & Median

by El Cucu » Thu Mar 19, 2009 1:10 pm
Vemuri wrote:If 2 sets of numbers P & Q have the same number of elements, is the mean of set Q lower than the mean of set P?

1. Set Q consists of consecutive even integers and set P consists of consecutive odd integers.

2. The median of set Q is higher than the mean of set P.
1. Insufficient ie, Q 2,4,6, P 1,3,5 or Q 2,4,6, P 5,7,9
2. Insufficient ie, Q 12,14,16, P 1,13,101

Together Q>P so C)

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by scoobydooby » Fri Mar 20, 2009 4:58 am
thanks so much for pointing out Avenus. I need to watch out. i keep getting tricked in ds..:(