Find x in the image above

Mathematics

1 answer:

Nikolay [14]3 years ago

5 0

Answer:

3.96

Step-by-step explanation:

3.3÷5=0.66

6×0.66=3.96

You might be interested in

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

Help help please answer this question and no link

arsen [322]

I hope this helps! May you have a great day today! ❤️