mokura wrote:

Hi,

Can you tell me how I would solve a question similar to the following?

Let's say I have the following list representing scores on an exam for 3 students

student: a b c

test 1: 4 5 6

test 2: 7 5 9

test 3: 4 2 1

how can I find which student had the biggest standard dev and the smallest?

I know this is very simple but I'm just confused when the list is a lot bigger what the quickest way would be.

Thanks!

The standard deviation of a set shows how much variation there is from the mean, how widespread a given set is. So, a low standard deviation indicates that the data points tend to be very close to the mean, whereas high standard deviation indicates that the data are spread out over a large range of values.Back to the question.

Scores of Student A {4, 7, 4} = {4, 4, 7}

Scores of Student B {5, 5, 2} = {5, 5, 2}

Scores of Student C {6, 9, 1}

Sets A and B are equally widespread, thus they will have the same SD. Set C is more widespread than these two so it will have the greatest SD.

Theory on Statistics and Sets:

math-standard-deviation-87905.htmlDS questions on Statistics and Sets to practice:

search.php?search_id=tag&tag_id=34PS questions on Statistics and Sets to practice:

search.php?search_id=tag&tag_id=55Hope it helps.

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