Help with this question, please! The answer with the red arrow is INCORRECT!! HELP ASAP!

A random sample of 144 recent donations at a certain blood bank reveals that 81 were type A blood. Does this suggest that the ac

Reptile [31]

Answer:

Null hypothesis: $p=0.4$

Alternative hypothesis: $p \neq 0.4$

$z=\frac{0.5625 -0.4}{\sqrt{\frac{0.4(1-0.4)}{144}}}=3.98$

$p_v =2*P(z>3.98)=0.0000689$

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

$\hat p=\frac{81}{144}=0.5625$ estimated proportion of people with type A blood

$p_o=0.4$ is the value that we want to verify

$\alpha=0.01$ represent the significance level

z would represent the statistic

$p_v{/tex} represent the p value Hypothesis to testWe want to test if the percentage of the population having type A blood is different from 40%.: Null hypothesis:[tex]p=0.4$

Alternative hypothesis: $p \neq 0.4$

the statistic is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

Replacing the info given we got:

$z=\frac{0.5625 -0.4}{\sqrt{\frac{0.4(1-0.4)}{144}}}=3.98$

Now we can calculate the p value with this probability taking in count the alternative hypothesis:

$p_v =2*P(z>3.98)=0.0000689$

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%

3 0

3 years ago

If you roll two number cubes ,what is the probability of their sum being 9 or higher?

bija089 [108]

Answer:

5/18

Step-by-step explanation:

When two cubes are rolled there are 36 possibilities

Each dice has 6 equally like outcomes so possibilities are

(1,1) (1,2) (1,3) (1,4) (1,5) (1,6)

(2,1) (2,2) (2,3) (2,4) (2,5) (2,6)

(3,1) (3,2) (3,3) (3,4) (3,5) (3,6)

(4,1) (4,2) (4,3) (4,4) (4,5) (4,6)

(5,1) (5,2) (5,3) (5,4) (5,5) (5,6)

(6,1) (6,2) (6,3) (6,4) (6,5) (6,6)

Now we look at the pair that has sum equal to 9

(3,6) (4,5) (5,4) (6,3) that has sum of 9

Probability of sum is 9 = $\frac{4}{36}$

we look at the pairs that has sum greater than 9

(4,6) (5,5)(5,6) (6,4)(6,5)(6,6)

Probability of sum greater than 9 = $\frac{6}{36}$

Probability of sum 9 or higher = P(sum 9) + P(greater than 9)

= $\frac{4}{36}+\frac{6}{36}= \frac{10}{36}=\frac{5}{18}$

4 0

4 years ago

What is 22b+3b simplified

ss7ja [257]

it's a simple addition:

22b + 3b =

25b

5 0

4 years ago

Please help me with this question.

xeze [42]

Answer: -3 4/15
Explanation: Combine multiplied terms into a single fraction

Subtract 3 from both sides of the equation

Simplify

Multiply all terms by the same value to eliminate fraction denominators

Simplify

End Up With -52/15

Turn into a equivalent fraction

End Up With -3 4/15

5 0

3 years ago

Write an equation to represent the scenario? car cost $3920, saved $500. if he saves $95 per week.

Orlov [11]

($ saved)+($ saves per week)x=($ cost)

$500+$95x=$3920

4 0

3 years ago