Question

At a certain coffee​ shop, all the customers buy a cup of coffee and some also buy a doughnut. The shop owner believes that the number of cups he sells each day is normally distributed with a mean of 330 cups and a standard deviation of 21 cups. He also believes that the number of doughnuts he sells each day is independent of the coffee sales and is normally distributed with a mean of 130 doughnuts and a standard deviation of 17.

​a) The shop is open every day but Sunday. Assuming​ day-to-day sales are​ independent, what's the probability​ he'll sell over 2000 cups of coffee in a​ week?

Answer 1

Answer:- () The shop owner be lives that the number of cups'he sells each day is nor mally distributed With a mean of Tu = 330|cups The standard deviation of 16 = 21) cups The number of doughnuts he sells each day is in depth of the coffee sales and is normally distributed With a mean of u-130 doughnuts. The standard deviation is 0:17 It is given that, the shop is open everyday. the number of Working days are independent and is 16 The population mean is Mc 6 (330) = 1980 The Standard deviation is or carcot -J36Waren) 6(400) : 52400 -148.9897) The probability he'll sell over 2000 cups of Coffee in a week is Plx>2000) = 1 - P(X5 2000)

= i-play = 48.9897 EP (240.40) -1-0.6554 10.3446