Question

So far this yearThe average tactile during dinner service at a restaurant is $52 with a standard deviation of $11 to reach a sales goal, The next 25 checks during dinner service must average at least $50 each what is the probability this restaurant reaches it it’s sales goal? Write your answers as a decimal rounded to three places

Answer 1

s=$\sigma/\sqrt n=11/5=2.2$

P(x>50)=1-P(x<50)

P(x<50)

z=$(x-\mu)/s$ =-2/2.2=-0.91

using table, P=0.18141

P(x>50)=1-0.18141=0.819