A random sample of 147 recent donations at a certain blood bank reveals that 87 were type A blood. Does this suggest that the actual percentage of type A donations differs from 40%, the percentage of the population having type A blood? Carry out a test of the appropriate hypotheses using a significance level of 0.01. State the appropriate null and alternative hypotheses.

The p value is lower than the significance level of 0.01. So then we have enough evidence to reject the null hypothesis and we can conclude that the true proportion of type A donations differs from 40%, the percentage of the population having type A blood

Step-by-step explanation:

Infomration given

n=147 represent the random sample taken

X=87 represent the people who are type A blood

estimated proportion of people with type A blood

is the value to verify

represent the significance level

z would represent the statistic

represent the p value

Hypothesis to test

We want to verify if type A donations differs from 40% so then the system of hypothesis are:  

Null hypothesis:  

Alternative hypothesis:  

The statistic for this case is given:

(1)  

Replacing the info given we got:

Now we can calculate the p value with this probability:

The p value is lower than the significance level of 0.01. So then we have enough evidence to reject the null hypothesis and we can conclude that the true proportion of type A donations differs from 40%, the percentage of the population having type A blood

step-by-step explanation:

first, eliminate the parenthesis:

3

x

+

2

−

4

x

second, group like terms:

3

x

−

4

x

+

2

third, combine like terms:

(

3

−

4

)

x

+

2

→

−

1

x

+

2

→

−

x

+

2

answer:

c. the third graph