Xr12-135 Duplicate bridge is a game in which players compete for master points. When a player receives 300 master points (some of which must be silver, red, and gold), he or she becomes a life master.

Because that title comes with a certificate that some people have framed the American Contract Bridge League is interested in knowing the status of nonlife masters. Suppose that a random sample of 80 nonlife masters was asked how many master points they have. The ACBL would like an estimate of the mean number of master points held by all nonlife masters. A confidence level of 90% is considered adequate in this case.