Question

I asked a random sample of 15 adults, aged 25 - 50, how many hours per week they spent playing video games. The responses were as follows:

7, 15, 3, 1, 2, 2, 0, 0, 10, 5, 1, 1, 2, 0, 2

With a mean of 3.4 and a standard deviation of 4.256, determine a 90% confidence interval.

Answer #1

We have given that,

Sample mean =3.4

Sample standard deviation =4.256

Sample size =15

Level of significance=1-0.90=0.1

Degree of freedom =14

t critical value is (by using t table)=
1.7613

Confidence interval formula is

=(1.46,5.34)

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