The number of pages per book on a bookshelf is normally distributed with mean 248 pages and standard deviation 21 pages. Using the empirical rule, what is the probability that a randomly selected book has less than 206 pages?

The probability is 0.0228

Step-by-step explanation:

We proceed by calculating the z-score value

Mathematically;

z-score = (x - mean)/SD

where x = 206, mean = 248 and SD = 21

Substituting these values, we have;

z-score = (206-248)/21 = -42/21 = -2

So the probability we want to calculate is;

P(z < -2)

We can use the standard normal distribution table for this;

P(z < -2) = 0.0228

step-by-step explanation:

x-intercept:

(

−

1

+

√

7

,

0

)

,

(

−

1

−

√

7

,

0

)

y-intercept:

(

0

,

−

6

)

yx = 36

step-by-step explanation:

cos f = opposite side/ hypotenuse

cos f = yw / yx

we know cos f = 4/9 and yw =16

4/9 = 16/yx

multiply each side by yx

4/9 yx = 16/ yx * yx

4/9 yx = 16

multiply each side by 9/4

9/4 * 4/9 yx = 16 *9/4

yx = 36