Paper 3 · Statistics5.3 Statistical hypothesis testing
The volume of drink in a can is Normally distributed with standard deviation 4 ml. The label says the mean volume is 330 ml. A trading standards officer measures a random sample of 20 cans and finds a mean of 328.6 ml.
Test, at the 5% level, whether the mean volume is less than 330 ml.
, , where is the mean volume of all cans.