Find the value of x.

Mathematics

1 answer:

Sav [38]3 years ago

4 0

Answer:

140

Step-by-step explanation:

the arce is equavelnt to point

You might be interested in

Psychology students at Wittenberg University completed the Dental Anxiety Scale questionnaire (Psychological Reports, August 199

fredd [130]

Answer:

a) $Z = 1.43$

b) There is a 48.696% probability that someone scores between a 10 and a 15 on the Dental Anxiety Scale is

Step-by-step explanation:

Normal model problems can be solved by the zscore formula.

On a normaly distributed set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a value X is given by:

$Z = \frac{X - \mu}{\sigma}$

Each z-score value has an equivalent p-value, that represents the percentile that the value X is.

In our problem, the mean score was 11 and the standard deviation was 3.5.

So, $\mu = 11$ , $\sigma = 3.5$ .

(a) Suppose you score a 16 on the Dental Anxiety Scale. Find the z-value for this score.

What is the value of Z when $X = 16$ ?

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{16 - 11}{3.5} = 1.43$

(b) Find the probability that someone scores between a 10 and a 15 on the Dental Anxiety Scale.

We have to find the percentiles of both of these scores. This means that we have to find Z when $X = 10$ and $X = 15$ . The probability that someone scores between a 10 and a 15 is the difference between the pvalues of the z-value of X = 10 and X = 15.