Assume the printer cartridges in average can print 12,000 pages with 800 pages as its standard deviation (H= 12000, o = 800), and it is a bell-shaped distribution for the number of pages (X) it can print before running of of ink.(X is a random variable, isn't it?) Using Emprical Rules to answer: What is the chance that your cartridger can print between 10,400 to 11,200 pages? That means in Math: P(10,400 < X < 11,200) = ? (ex., if the answer is 6.5%, write only 0.065, ignore the % sign).