Question

The label on a companies energy drink claims that they contain 250 mg/oz. The mean caffeine concentration of 15 randomly sampled drinks was 267, with a standard deviation of 12.1. Was a two-tailed test used to assess the alternative hypothesis? What is the P-value?

Answer 1

Solution :

Given that,

Population mean = = 250

Sample mean = = 267

Sample standard deviation = s = 12.1

Sample size = n = 15

This is a two tailed test.

The null and alternative hypothesis is,

Ho: 250

Ha: 250

The test statistics,

t = ( - )/ (s/)

= ( 267 - 250 ) / ( 12.1 / 15 )

= 5.441

P- Value = 0.0001