A manager of a warehouse would like to know how many errors are made when a product serial number is read by a barcode reader 6 samples are collected of the number of scanning errors 3614 2139 11 and 2 errors per 1000 scans each what is the mean and the standard deviation of the 6 samples

If 1/√5+1/√5+1=p+q√r , find the values of p, q and r

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?

What is the area of the shaded sector?