what is the the range in this data, the variance, and the standard deviation

Question

0,73,93,165,193,199,229,234,240,245,257,268,332,380,385

I need the range formula and how to

the variance formula and how to

And the deviation formula and how to

Answer 1

The range is the difference between the highest and lowest data: 385-0=385.

To find the variance first find the average (mean) of all the data. Add the data values together and then divide by the amount of data (15 in this case): 3293/15=219.53.

We subtract the mean from each datum in the set and square the result. Then we add together all of these and divide by 15: 10711.58 (approx). Another way to do this is to add up all the squares of the data, divide the result by 15, then subtract the square of the mean. 

We take the square root of this variance to get the standard deviation: 103.50 (approx).