I'm studying stats independently online from my university so don't have a teacher to ask how to finish these question. Any help would be much appreciated. Because I dnt know what im doing wrong and I just cant figure it out. thank you.

Problems:

A probability distribution has two requirements:

1)

2)

a)Is this a probability distribution? why or why not?

x|p(x)

------

0|0.2

1|0.5

2|0.4

3|0.3

b) does p(x)= x/3 (x=0,1,2) determine a probability distribution?

customer waiting time in bank lines:

a (single line) 6.5, 6.6, 6.7, 6.8, 7.1, 7.3, 7.4, 7.7, 7.7, 7.7

b(individual lines) 4.2, 5.4, 5.8, 6.2, 6.7, 7.7, 7.7 ,8.5 , 9.3 , 10.0

a)find the mean, median, mude, variance, standard deviation and rang of each data set. which set appears to be the fastest?

b)perform a hypothesis test to see if one method appears to be more efficient that other. hinttest 2 means). show the null and alternative hypotheses, the critical valve at alpha= 0.05, the test statistic, and the p-value. lastly, show (explain) your conclusion.