1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
gregori [183]
3 years ago
14

Using the z table, find the critical value for a=0.024 in a left tailed test

Mathematics
1 answer:
natita [175]3 years ago
7 0

Answer:

Critical value is -1.98.

Step-by-step explanation:

Given:

The value of alpha is, \alpha=0.024

Now, in order to find the critical value, we need to subtract alpha from 1 and then look at the z-score table to find the respective 'z' value for the above result.

The probability of critical value is given as:

P(critical)=1-\alpha=1-0.024=0.976

So, from the z-score table, the value of z-score for probability 0.976 is 1.98.

Now, in a left tailed test, we multiply the z value by negative 1 to arrive at the final answer. We do so because the area to the left of mean in a normal distribution curve is negative.

So, the z-score for critical value 0.024 in a left tailed test is -1.98.

You might be interested in
5. Tyra has 12 cups of sugar. If r is the amount of sugar needed for
MrMuchimi

Answer:

it depends how much oatmeal she has -.-

Step-by-step explanation:

JKJK I think its ten...

6 0
2 years ago
A doctor released the results of clinical trials for a vaccine to prevent a particular disease. In these clinical​ trials, 200,0
CaHeK987 [17]

Answer:

1) No, there is  not  enough evidence to support the claim that the vaccine was effective (P-value=0.104) .

The null and alternative hypothesis are:

H_0: \pi_1-\pi_2=0\\\\H_a:\pi_1-\pi_2< 0

being the subindex 1 for the experimental group and subindex 2 for the control group.

2) Test statistic z=-1.26

Step-by-step explanation:

This is a hypothesis test for the difference between proportions.

The claim is that the vaccine was effective.

Then, the null and alternative hypothesis are:

H_0: \pi_1-\pi_2=0\\\\H_a:\pi_1-\pi_2< 0

The significance level is 0.01.

The sample 1 (experimental group), of size n1=100000 has a proportion of p1=0.0002.

p_1=X_1/n_1=21/100000=0.0002

The sample 2 (control group), of size n2=100000 has a proportion of p2=0.0003.

p_2=X_2/n_2=30/100000=0.0003

The difference between proportions is (p1-p2)=-0.0001.

p_d=p_1-p_2=0.0002-0.0003=-0.0001

The pooled proportion, needed to calculate the standard error, is:

p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{21+30}{100000+100000}=\dfrac{51}{200000}=0.00026

The estimated standard error of the difference between means is computed using the formula:

s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.00026*0.99974}{100000}+\dfrac{0.00026*0.99974}{100000}}\\\\\\s_{p1-p2}=\sqrt{0+0.0000000025}=\sqrt{0.0000000051}=0.000071

Then, we can calculate the z-statistic as:

z=\dfrac{p_d-(\pi_1-\pi_2)}{s_{p1-p2}}=\dfrac{-0.00009-0}{0.000071}=\dfrac{-0.00009}{0.000071}=-1.26

This test is a left-tailed test, so the P-value for this test is calculated as (using a z-table):

P-value=P(z

As the P-value (0.104) is bigger than the significance level (0.01), the effect is not significant.

The null hypothesis failed to be rejected.

There is  not  enough evidence to support the claim that the vaccine was effective.

6 0
3 years ago
Select the correct answer.
skad [1K]

Answer:

D

Step-by-step explanation:

7 is it because it is positive

6 0
3 years ago
7r-5r+8=9r+8-r translate to an equation, then solve
pshichka [43]

Answer:

r=0

Step-by-step explanation:

7r-5r+8=9r+8-r

This is already an equation

Combine like terms

2r+8 = 8r+8

Subtract 2r from each side

2r-2r +8 = 8r-2r +8

8 =6r+8

Subtract 8 from each side

8-8 = 6r+8-8

0 = 6r

Divide by 6

0/6 = 6r/6

0 =r

7 0
3 years ago
I provided it in the picture, please help!
Goshia [24]
The answer would be D.
7 0
2 years ago
Other questions:
  • Tina has 3 stacks of 5CDs on each of 3 shelves.how nany CDs does she have
    8·2 answers
  • which of the following is equivalent to the equation 2(x-3)=5(x+1)? A. 2x-3=5x+1 B. 2x-6=5x C.2x-6=5x+5 D.2x-3=5x If a= 0, which
    12·1 answer
  • Solve -np-80&lt;60 for n. Show your work.<br><br> Solve 2a-5d=30 for d. Show your work.
    5·1 answer
  • Has to be evaluated in scientific notation
    9·1 answer
  • Which of the following lines are parallel to 2Y - 3X = 4?
    15·1 answer
  • Is 8 4/9 a rational number
    5·2 answers
  • Simplify the expression
    13·2 answers
  • - Joy and John MacAllister have agreed to purchase a house for $79,900. First
    9·1 answer
  • In an inequality, -2.5 is the lesser number. What is the position of the other number on the horizontal number line in relation
    6·2 answers
  • I need help i dont understand it. its due in literally 2 hrs.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!