This is not a random sample since she is outside of a pet store and the probability of people owning a dog coming out of that store is very very high. If she went around the neighborhood and knocked on people’s door and asked if they had a dog or not would be random sample.

6 0

4 years ago

Find the margin of error for a 90% confidence interval when the standard deviation is LaTeX: \sigma= 50????=50 and LaTeX: n = 25

Murrr4er [49]

Answer:

The margin of error for a 90% confidence interval is 16.4

Step-by-step explanation:

We are given the following in the question:

Sample size, n = 25

Standard deviation = 50

$z_{critical}\text{ at}~\alpha_{0.10} = \pm 1.64$

Margin of error =

$z_{critical}\times \dfrac{\sigma}{\sqrt{n}}$

Putting the values, we get,

$1.64\times \dfrac{50}{\sqrt{25}} = 16.4$

Thus, the margin of error for a 90% confidence interval is 16.4

8 0

4 years ago

If b < 0 and a/b > c/b, then what is the relationship between a and c?

serg [7]

Answer:

a < c

Step-by-step explanation:

<u>Given inequality:</u>

a/b > c/b

<u>Since b is negative, when multiplied by b, the inequality changes to opposite direction:</u>

b(a/b) < b(c/b)
a < c

3 0

3 years ago