Just 6-8 pls n thx.......

An IQ test is designed so that the mean is 100 and the standard deviation is 18 for the population of normal adults. Find the sa

melisa1 [442]

Answer:

At least 98 people need to be sampled. It is not a huge number, that is, it is not difficult to sample 98 people, so it is a reasonable sample size for a real world calculation.

Step-by-step explanation:

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

$\alpha = \frac{1-0.9}{2} = 0.05$

Now, we have to find z in the Ztable as such z has a pvalue of $1-\alpha$ .

So it is z with a pvalue of $1-0.05 = 0.95$ , so $z = 1.645$

Now, find the margin of error M as such

$M = z*\frac{\sigma}{\sqrt{n}}$

In which $\sigma$ is the standard deviation of the population and n is the size of the sample.

In this question:

We need a sample size of at least n.

n is found when M = 3. We have that $\sigma = 18$ .

$M = z*\frac{\sigma}{\sqrt{n}}$

$3 = 1.645*\frac{18}{\sqrt{n}}$

$3\sqrt{n} = 1.645*18$

Simplifying by 3

$\sqrt{n} = 1.645*6$

$(\sqrt{n})^{2} = (1.645*6)^{2}$

$n = 97.41$

Rounding up,

At least 98 people need to be sampled. It is not a huge number, that is, it is not difficult to sample 98 people, so it is a reasonable sample size for a real world calculation.

8 0

3 years ago

The set of ordered pairs below represents a linear function. Find the rate of change. {(1,4), (2,6), (3,8), (4,10)} The

Finger [1]

Answer:

(1,2)

Step-by-step explanation:

6 0

4 years ago

24 students and Jamal's class are wearing tennis shoes there are 30 students in this class your mom says that 70% of this class

mel-nik [20]

Im not sure if i am understanding the question correctly...

If you are asking if Jama's mom is correct, then no. she is wrong. this is because

if you take the proportion, (is/of)=(%/100) you get (x/30)=(70/100). You then solve for x which in this case would be 21 students are wearing tennis shoes.

Hope this helps.

3 0

3 years ago

keiko has seven colors of lanyard. she uses three different colord to make a keychain. how many different combiantions can she c

Drupady [299]

She can make 12 different combinations.
If she used three different colors for the keychain, there's still 4 other colors left.
4 x 3 = 12

7 0

3 years ago

Read 2 more answers

The graph of F(x) , shown below, resembles the graph of G(x) = x ^ 2 , but it has been changed somewhatWhich of the following co

NNADVOKAT [17]

Answer:

B.

Step-by-step explanation:

Since we are moving the graph f(x) to the right 2 and down 1 with a reflection over the x-axis, we modify a, h, and k in f(x) = a(bx - h)² + k:

We would get f(x) = -(x - 2)² - 1 as our answer.

7 0

4 years ago