The mccormick hardware store places one order for riding lawn mowers each february. The lawn mowers being purchased this year cost $300 and sell for $425. In the past, mccormick has always been able to sell all its surplus mowers during the september "end-of-summer" sale. The sales price for any surplus mowers this year is $250. If the following probability distribution for demand is assumed, how many mowers should be ordered?.