In: Statistics and Probability
a)In order to determine the average price of hotel rooms in georgia, a sample of 63 hotels were selected. It was determined that the test statistic (z) was $1.74. We would like to test whether or not the average room price is significantly different from $110. Population standard deviation is known to us.Compute the p-value.
b)In order to determine the average price of hotel rooms in Atlanta, a sample of 36 hotels were selected. It was determined that the average price of the rooms in the sample was $108.4. The population standard deviation is known to be $13. We would like to test whether or not the average room price is significantly different from $110.Compute the test statistic.
c)A sample of 36 account balances of a credit company showed an average balance of $1,179 and a standard deviation of $136. You want to determine if the mean of all account balances is significantly greater than $1,150. Use a 0.05 level of significance. Assume the population of account balances is normally distributed.Compute the test statistic.
Solution:
a)
n = 63
test statistic (z) = $1.74
two tailed test
P-value = 0.0819
P-value > = 0.05 , fail to Reject H0
the average room price is not significantly different from $110
b)
= $108.4
= $13
n = 25
Hypothesis:
H0 : $110
Ha : $110
Test Statistic:
Z = ( - ) / ( /n)
Z = (108.4- 110) / ( 13/ 25)
Z = -0.615
P-value = 0.539
P-value > = 0.05 , fail to Reject H0
the average room price is not significantly different from $110
c)
= $1,179
s = $136
n = 36
a.) Hypothesis:
H0 : $1,150
Ha : $1,150
Test Statistic:
t = ( - ) / (s /n)
t = (1,179- 1,150) / ( 136/ 36)
t = 0.153
P - value = 0.4396
P-value > = 0.05 , fail to Reject H0
the mean of all account balances is not significantly greater than $1,150.