Answer: No, this is not necessarily evidence that the proportion of Americans who are afraid to fly has increased.
Step-by-step explanation:
Since we have given that
n = 1400
x = 154
So, [tex]\hat{p}=\dfrac{154}{1400}=0.11[/tex]
and p = 0.10
So, hypothesis would be
[tex]H_0:\hat{p}=p\\\\H_a:\hat{p}>p[/tex]
So, the test statistic value would be
[tex]z=\dfrac{\hat{p}-p}{\sqrt{\dfrac{p(1-p)}{n}}}\\\\z=\dfrac{0.11-0.10}{\sqrt{\dfrac{0.1\times 0.9}{1400}}}\\\\z=\dfrac{0.01}{0.008}\\\\z=1.25[/tex]
At 5% level of significance,
critical value would be 1.96.
Since 1.96>1.25.
so, we will accept the null hypothesis.
Hence, no, this is not necessarily evidence that the proportion of Americans who are afraid to fly has increased.