A research report claims that 20 of all individuals use Fire
A research report claims that 20% of all individuals use Firefox to browse the web. A software company is trying to determine if the proportion of their users who use Firefox is significantly different from 0.2. In a sample of 200 of their users, 32 users stated that they used Firefox. Using this data, conduct the appropriate hypothesis test using a 0.05 level of significance.
a) What are the appropriate hypotheses?
A.)H0: p = 0.2 versus Ha: p < 0.2
A.)H0: p = 0.2 versus Ha: p 0.2
C.)H0: = 0.2 versus Ha: > 0.2
D.)H0: p = 0.2 versus Ha: p > 0.2
b) What is the test statistic? Give your answer to four decimal places.
c) What is the P-value for the test? Give your answer to four decimal places.
d) What is the appropriate conclusion?
A.)Fail to reject the claim that the Firefox proportion is 0.2 because the P-value is larger than 0.05.
B.)Conclude that the Firefox proportion is not 0.2 because the P-value is larger than 0.05.
C.)Fail to reject the claim that the Firefox proportion is 0.2 because the P-value is smaller than 0.05.
D.)Conclude that the Firefox proportion is not 0.2 because the P-value is smaller than 0.05.
Solution
a)
A.)H0: p = 0.2 versus Ha: p ? 0.2
b)
p = 32/200 = 0.16
z= 0.16 - 0.20 / srqt(0.20*0.80 / 200 )
z= -0.04 / 0.02828 = -1.4142
c)
p value : 0.0793
d)
if p value is greater than significance level we fail to reject Ho
if p value is lower than significance level we reject Ho
A.)Fail to reject the claim that the Firefox proportion is 0.2 because the P-value is larger than 0.05.
