SOLUTION: Coffee with Meals A researcher wishes to determine the number of cups of coffee a customer drinks with an evening meal at a restaurant. Find the mean, vari- ance, and standard devi

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Question 1170287: Coffee with Meals A researcher wishes to determine the number of cups of coffee a customer drinks with an evening meal at a restaurant. Find the mean, vari- ance, and standard deviation for the distribution. 0 1 2 34 P(X) 0.31 0.42 0.21 0.04 0.02
What is the expectation of the information provided above ?
Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website!
0--0.31---product 0--------------squared deviation*probability=1.12^2*0.31=0.3889
1--0.42-----------0.42-----------0.0144*0.42=0.006048
2--0.21-----------0.42-----------0.88*0.21=0.1848
3--0.04----------0.12------------1.88^2*0.04=0.1414
4--0.04----------0.16------------2.88^2*0.04=0.3318
sum is expected value, and that is 1.12 cups, which is the mean
variance is sum of squared deviations * p(x)=1.0529 cups^2
sd is sqrt(V)=1.026 cups