Question

Leema's test scores in chemistry are 80, 95, 88, 92, and 100. Find the mean and standard deviation of the data. If necessary, round to the nearest tenth. Mean: ______ Standard deviation: ______

Answer 1

Mean is 91

SD=6.8 to the nearest tenth.

Explanation:

Leema's test scores in chemistry are 80, 95, 88, 92, and 100.

We want to find the mean and standard deviation.

The mean is given by:

`\bar X=(80+95+88+92+100`)/(5)`

`\bar X=(455`)/(5)=91`

The standard deviation is given by:

`SD=\sqrt{(\sum(x-\bar X)^2)/(n) }`

`SD=\sqrt{((80-91)^2+(95-91)^2+(88-91)^2+(92-91)^2+(100-91)^2)/(5) }`

`SD=\sqrt{(1140)/(25) }`

SD=6.8 to the nearest tenth.