prep3

[vivek.kapoor83]

it shld be D.
1.clear
2. Avg = sum/no of ppl/
both are given
so IMO D but wrong

[krazy800]

Vivek,
I think answer should be A

Statement 1 works out as u have pointed..

in Statement 2 though sum is given u don't have info abt no. of people.. so not sufficient.

[vittalgmat]

krazy800,
If 2 is not sufficient, then on the same grounds, I would argue 1 is not sufficient either. coz we dont know n. But since the question itself asks us to find avg of n ppl, 2 is sufficient. Otherwise, I dont know what differentiates 1 from 2.

1 is an avg of avgs vs 2 a simple avg.

Pls explain why you said that 2 is insufficient.

thanks
-V

[vivek.kapoor83]

krazy800,
If 2 is not sufficient, then on the same grounds, I would argue 1 is not sufficient either. coz we dont know n. But since the question itself asks us to find avg of n ppl, 2 is sufficient. Otherwise, I dont know what differentiates 1 from 2.

1 is an avg of avgs vs 2 a simple avg.

Pls explain why you said that 2 is insufficient.

thanks
-V

I agree with Vital.....Avg = sum/no. of people.
Sum of height is given and no. of people = n. So, we can find out.
IMO D

[krazy800]

Vittal,
in statement 1: 'n' in both numerator and denominator..so n cancels out

Statement 2 .. i agree we know the sum of heights but the no of people n is still a variable so we cannot get a definitive answer (Average). therefore insufficient..

I still go with A..

Guyz any thoughts abt this problem is greatly appreciated!

[stop@800]

Its certainly A

A
the n will cancel
n/3 ppl have height x
2n/3 ppl have height y
so we can easily find average

B
total height is given but no of ppl are not given
so we can not solve

Difference between A and B
In A, we can find total height of n ppl in terms of n
so n and n can cancel
but in B
we have total height as a number
and the n of denom can not cancel.


Let me know if you need more detailed explanation!!

[mental]

IMO A
same as stop and krazy