A gas station manager thinks the average motorist changes their oil less than the recommended two times per year. In a survey 15 car owners were asked how many times they changed their oil in the past year. Here are the results:

1 1 2 1 2
2 0 1 0 1
2 3 1 3 0

The value of the test statistic is equal to _____________ ? (answer between two and four decimals)

2 answers

What test statistic are you seeking? Mean? Mode? Median? Standard deviation?

Mean = μ = (Σx)/n = 20/15 = 1.333

Is that what you were seeking?
1.55