Answer:
Null hypothesis:
Alternative hypothesis:
Since the p value is very low compared to the significance level we have enough evidence to reject the null hypothesis and we can conclude that the true percent of people with type A of blood is significantly different from 0.4 or 40%
Step-by-step explanation:
Information given
n=144 represent the random sample taken
X=81 represent the number of people with type A blood
estimated proportion of people with type A blood
is the value that we want to verify
represent the significance level
z would represent the statistic
Alternative hypothesis:
the statistic is given by:
(1)
Replacing the info given we got:
Now we can calculate the p value with this probability taking in count the alternative hypothesis:
Since the p value is very low compared to the significance level we have enough evidence to reject the null hypothesis and we can conclude that the true percent of people with type A of blood is significantly different from 0.4 or 40%