score intervals

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score intervals

by anant03 » Fri Sep 04, 2015 9:23 am
Score No. of scores
intervals

50-59 2
60-69 10
70-79 16
80-89 27
90-99 18

The table above shows the distribution of test scores for a group of management trainees.
Which score interval contain the median of the 73 scores?

(a) 60-69
(b) 70-79
(c) 80-89
(d) 90-99
(e) It cannot be determined from the information given

OAC

Please advise[/spoiler]
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by Brent@GMATPrepNow » Fri Sep 04, 2015 9:32 am
This link shows a better version of the data table: https://www.beatthegmat.com/gmat-prep-te ... 78285.html
50-59 2
60-69 10
70-79 16
80-89 27
90-99 18

The table above shows the distribution of test scores for a group of management trainees.
Which score interval contain the median of the 73 scores?

(a) 60-69
(b) 70-79
(c) 80-89
(d) 90-99
(e) It cannot be determined from the information given
Since we have an ODD number of values, the median will be the MIDDLEMOST value. In other words, if we arrange all 73 values in ASCENDING order, the median will be the 37th value (i.e., 36 values are below and 36 values are above).

The table says the first 2 scores in the 50-59 range. So, the 1st and 2nd values will be in the 50-59 range.
The table says the next 10 scores in the 60-69 range. So, 3rd to 12th values will be in the 60-69 range.
The table says the next 16 scores in the 70-79 range. So, the 13th to 28th values will be in the 70-79 range.
The table says the next 27 scores in the 80-89 range. So, the 29th to 45th values will be in the 80-89 range.

As we can see, the 37th value must be in the 80-89 range.

Answer: C

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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