How to find the median from a histogram

cleocj1000

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How would I go about making an estimate of the median from the graph in the image?
 

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First, for a question like this ("which of the following ...)", the choices given are an essential part of the problem, so you have to include them all. There may be several possible answers, with only one of them in the list.

Now, do you know what median means? It is a number such that equal numbers of data points are above and below it. So you can add up the frequencies of all the classes, and then count up until the cumulative frequency is half of that. Then you'll have to do a little thinking.

I would start by turning the histogram into a table of values:

5-10: 7​
10-15: 8​
...​
 
First, for a question like this ("which of the following ...)", the choices given are an essential part of the problem, so you have to include them all. There may be several possible answers, with only one of them in the list.

Now, do you know what median means? It is a number such that equal numbers of data points are above and below it. So you can add up the frequencies of all the classes, and then count up until the cumulative frequency is half of that. Then you'll have to do a little thinking.

I would start by turning the histogram into a table of values:

5-10: 7​
10-15: 8​
...​
I understand how to estimate the median from the graph, but my answer choice was c) 24 which the textbook states is an incorrect answer, as they chose answer b) 34, so I would like to know if my calculations for the mean were wrong. I solved this by adding all the frequency values which is 52, dividing by 2 and then finding the interval where the 26th value would lie which is between 20-24.
I apologize for the cropped answers, but the answer choices are
a. 19years
b. 34years
c. 24years
d. 39years
e. 29years
 
I understand how to estimate the median from the graph, but my answer choice was c) 24 which the textbook states is an incorrect answer, as they chose answer b) 34, so I would like to know if my calculations for the mean (?) were wrong. I solved this by adding all the frequency values which is 52, dividing by 2 and then finding the interval where the 26th value would lie which is between 20-24.
I apologize for the cropped answers, but the answer choices are
a. 19years
b. 34years
c. 24years
d. 39years
e. 29years
Thanks. This is what you should have told us from the start! so often the real issue is an error in the book's answer, but we don't learn that until we've wasted time explaining what the asker already knew ...

Any number in the range 20 to 24 should be acceptable, so 24 is the correct answer. (I assume you didn't mean to say "mean" above.)

I suspect they made a typo (or else a real error!) in saying 34. Looking at the graph, there are 40 homes 34 or less years old, and only 12 older than 34, so that makes no sense at all.
 
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