abdullahkhan19 wrote:

Hello,

I dont have the multichoice answer available. Please help me understand the problem.

Q:125 passengers commute everyday. Is the median commute per day less than 40km ?

1) 62 passengers commute within 35 kms from their house

2) 63 passengers commute within 45 kms from their house

What I understand from this question is :

what is the average communte. So can we calculate it like this --->

62*35 = 2170

63*45 = 2835

then add them up and divide it by 125 to get the answer 40.04

So the median commute per day is not less than 40. .. Answer

IS IT RIGHT?

Thanks

You are calculating the mean (average). The question asks for the median, not the average.

Here we have a set of 125 values. The median, the number in the middle of our set, will be the 63rd largest (or 63rd smallest - that's the same thing). We know from Statement 1 that 62 values are less than 35, but we don't know about the 63rd smallest value. From Statement 2, we know that we have 63 values which are less than 45, but we don't know if the 63rd smallest is less than 40. Even combined, while we know the 63rd smallest is somewhere between 35 and 45, we don't know if it's less than 40, so the answer is E.

_________________

Nov 2011: After years of development, I am now making my advanced Quant books and high-level problem sets available for sale. Contact me at ianstewartgmat at gmail.com for details.

Private GMAT Tutor based in Toronto