Question

Question #53192

Answer 1

Assumption: You meant 'average'

`-10.35` degrees `larr` good practise to include units of measurment

Explanation:

`color(blue)("Answering the question")`

To calculate average (mean) you add up all the values.

You then divide that answer (the sum) by the count of how many values you have.

Count = 4

The sum:
`-12.1`
`-color(white)("d")7.8`
`-14.3`
`ul(-color(white)("d")7.2 larr" Add up"`
`-41.4`

So the average is `-41.4-:4 = -10.35`
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`color(blue)("The teaching bit - explaining what an average is.")`

There are in fact 3 types of average but only one mean. So it is better to use the word 'mean'; which is what we have just calculated.

The mean is that single value which, if you multiply it by the count of given values, will give you the same sum as adding up all the other numbers

That is:

Count is 4

The sum:
`-12.1color(white)("dddddddddddddd")-10.35`
`-color(white)("d")7.8color(white)("dddddddddddddd")-10.35`
`-14.3color(white)("dddddddddddddd")-10.35`
`ul(-color(white)("d")7.2 larr" Add up"rarrcolor(white)("d")-10.35`
`-41.4color(white)("dddddddddddddd")-41.40`

Mean `=("Sum")/("count")`