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
IRINA_888 [86]
3 years ago
14

A cognitive psychologist wants to know whether memory performance is changed by old age. She randomly selects 7 elderly individu

als and finds that their mean score on a standardized memory test equals 418.2. Scores on the standardized test in the general population are distributed normally with a mean equal to 465.6 and a standard deviation equal to 53.6 . Is there sufficient evidence to conclude that memory performance for elderly individuals differs from that of the general population
Mathematics
1 answer:
defon3 years ago
6 0

Answer:

z = \frac{418.7-465.6}{\frac{53.6}{\sqrt{7}}}= -2.340

Now we can calculate the p value with the following probability

p_v =2*P(z

If we use the commonly significance level of 0.05 we see that the p value is lower than these values we can conclude that the true mean is different from the value of 465.6 at 5% of significance

Step-by-step explanation:

Data provided

\bar X=418.7 represent the mean score on the standardized memory test

\sigma=53.6 represent the population standard deviation

n=7 sample size    

\mu_o =465.6 represent the value that we want to verify

z would represent the statistic

p_v represent the p value

System of hypothesis

We are interested to check if the memory performance for elderly individuals differs from that of the general population (mean different from 465.6), the system of hypothesis are then:

Null hypothesis:\mu = 465.6    

Alternative hypothesis:\mu \neq 465.6    

Since we know the population deviation we can use the z statistic from the z test for the true mean:

z =\frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}} (1)    

Replacing the info given we got:

z = \frac{418.7-465.6}{\frac{53.6}{\sqrt{7}}}= -2.340

Now we can calculate the p value with the following probability

p_v =2*P(z

If we use the commonly significance level of 0.05 we see that the p value is lower than these values we can conclude that the true mean is different from the value of 465.6 at 5% of significance

You might be interested in
10.
yan [13]

Answer:

D. y = -5^x – 27

Step-by-step explanation:

Find the negative reciprocal of the slope of the original line and use the point-slope formula  y − y 1 = m ( x − x 1 )  to find the line perpendicular to  − x + 5 y = 14 .

y = − 5 x − 27                         PERPENDICULAAR

...................................................................................................................................................

Find the slope of the original line and use the point-slope formula  y − y 1 = m ( x − x 1 )  to find the line parallel to  − x + 5 y = 14 .

y = 1 /5 x − 1                             PARALLEL

7 0
3 years ago
What number is 30% of 20%
vfiekz [6]
0.06 or you can just put 6.

Basically, you have to multiply 30% x 20.

Glad I could help☺️
4 0
3 years ago
Read 2 more answers
Three expressions equivalent to the following: -90x + 60
Deffense [45]

Answer:

33beacuse you i have -90×+60=9×6=369-63

3 0
3 years ago
Ill give brainliest if correct
Firlakuza [10]

Answer:

The answer is t/3=20

The right diagram is the one that has the orange boxes with 20s and has a t on top

8 0
3 years ago
Read 2 more answers
Kyle and Michael run a lap around a track. Kyle gets a 50 meter head start and runs 3 meters per second. Michael runs at a speed
DanielleElmas [232]

First, you need to put both equations in slope intercept form

Kyle: y=3x+50, because he runs 3 meters/second and he gets a 50 meter head start

Michael: y=4x

I think the answer would be 50 seconds

hope this helps

4 0
3 years ago
Read 2 more answers
Other questions:
  • Tony is in charge of the concession stand. he charges $4.00 for two hot dogs and two sodas. he charges $4.50 for three hot dogs
    15·2 answers
  • Evaluate the given expression for x =-5.<br> -3x^2+7x+29<br><br> So what should be the answer
    12·2 answers
  • A volleyball player has a a assists per game during a 5 game match. The volleyball player has 30 assists during the entire match
    7·2 answers
  • A scout troop is collecting aluminum cans to raise money. They have collected 150 lbs. of aluminum for which they can get 80 cen
    10·1 answer
  • Solve the triangle. Round your answers to the nearest tenth.
    14·1 answer
  • Me ajudem pfvr!!!!....
    8·1 answer
  • Please find the answer yo 749/d * d/749 = 1
    11·1 answer
  • I NEED THIS ASAP I HAVE TROUBLE WITH IT PLEASEEEEEEEEEEE!!!!!!!!
    11·2 answers
  • Reduce the following fraction to simplest terms 24/3 12/3
    9·1 answer
  • If a pair of consecutive interior angles are congruent, what is the measure of each angle?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!