Question

Statistics question. Picture attached.

Answer 1

I don't see how the mean is $19.47 or how the median is $19.59. I am getting $17.55 for the mean. How would this work?

Answer 2

@jim_thompson5910 @kropot72 @ganeshie8 @whpalmer4 @dan815 @thomaster @completeidiot

Answer 3

Okay, for the mean, you multiply the midpoint of each range by the sales for that range, sum over all the ranges, divide by the total number of sales.

\[\frac{(51*2.5+184*7.5+241*12.5+1468*17.5+1339*22.5+255*27.5+98*32.5+14*37.5)}{(51+184+241+1468+1339+255+98+14)}\]

Answer 4

That's exactly what I did but I didn't get $19.59

Answer 5

0.0, lemme do it again, sec

Answer 6

yes i got 19.47 lol. I probably messed up the numbers while doing the calculations before. Now, how about the median? That's only thing I don't seem to get @whpalmer4

Answer 7

@whpalmer4 ?

Answer 8

Yeah, I'm not quite sure how you find the median here. I counted up the data points, wrote them all out on a really wide piece of paper, and averaged the two in the middle, but that didn't give me the right answer :-)

Answer 9

Did you get 17.5 for the median? @whpalmer4

Answer 10

well, the two middle data points fall in the 15-20 bin, by my calculation, so yes. but I have no confidence that is correct.

Answer 11

Because the way I thought we would do it is using the midpoints of the interval correct? After adding up all the frequencies, the median should be the average of the 1825th and the 1826th terms, both of which are from the 15-20 interval, so both should be 17.5. Averaging the two terms gets us 17.5. So how is one supposed to get 19.59? 0.0

Answer 12

@whpalmer4

Answer 13

well, I agreed that that was my first instinct about how you would compute the median, but it doesn't seem to be correct.

Answer 14

I haven't had any luck finding a similar example where one might actually learn how this is to be done...

Answer 15

yea...how else would you 0,o I mean the median is the middle term when the data is arranged in increasing order. Here we aren't given the data so we need to use midpoints. The midpoints give us 17.5 and not 19.59, I mean how do you even get 19.59 lol.

Answer 16

??? wat u gais tink

Answer 17

this median is calculated a big different

Answer 18

think about the number of cds being sold