The life expectancy of a laserprinter toner cartridge varies considerably, according to the toner and drum type and how the cartridge is used. Printed pages containing lots of graphics require more toner, whereas pages with mostly text require considerably less toner. Page coverage is usually measured as a proportion (or percentage). For example, a typical text page has approximately 0.050.05 coverage. A random sample of printed pages from an office printer was obtained, and the page coverage was carefully measured.

Is there any evidence to suggest the data are from a nonnormalpopulation?

Find the three symmetric intervals about the mean, (,+),(xs,x+s), (2,+2),(x2s,x+2s), and(3,+3).and(x3s,x+3s).

(Use decimal notation. Round your answers to two decimal places. Give your answers as intervals in the form (,).(,). Note that x denotes the sample mean and s denotes the sample standarddeviation.)

(,+)=

(2,+2)= (3,+3)=

Find the actual proportion of observations in the interval(,+).interval(xs,x+s).

(Use decimal notation. Round your answer to two decimalplaces.)

proportion: