Paper 7 May/June 2010 MATHEMATICS (9709/71) A Levels
لطفا برای اطمینان از عملکرد و تجربه بهتر از مرورگرهای مدرن و به روز مانند کروم یا فایرفاکس استفاده کنید.

The masses of sweets produced by a machine are normally distributed with mean $\mu $ grams and standard deviation 1.0 grams. A random sample of 65 sweets produced by the machine has a mean mass of 29.6 grams.
a) Find a 99% confidence interval for $\mu $.
The manufacturer claims that the machine produces sweets with a mean mass of 30 grams.
b) Use the confidence interval found in part (a) to draw a conclusion about this claim.