The population must have a normal distribution.

2. find the area of the shaded region. The graph depicts that standard normal distribution with mean 0 and standard deviation 1.

M: 0 δ: 1

Z: 1.13= .8708

2ND DIST. #2

LOWER: -999999

UPPER: 1.13

U: 0 δ: 1

=.8707618393

3. Shaded area is 0.0694

0.0694

-1

= -.9306 = 1.48 get this by looking at z score area on the chart

4. shaded area is 0.0901

0.0901

-1

= -1.34

5. Find the indicated Z score. The graph depicts the standard normal distribution with mean 0 and standard deviation 1. shaded are is 0.4013

2nd dist. #3

Area: 0.4013

U: 0 δ: 1

= -.24998 rounded to -0.25

6. If Z is a standard normal variable, find the probability.

The probability that Z lies between 0.7 and 1.98

2nd dist. #2

LOWER: .7

UPPER: 1.98

U: 0 δ: 1

= .2181

7. find the area of the shaded region. The graph depicts IQ scores of adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15.

2nd dist. #2

LOWER: 85

UPPER: 125

U: 100 δ: 15

= .79355 = .7936

8. SOLVE THE PROBLEM. ROUND TO THE NEAREST TENTH UNLESS INDICATED OTHERWISE.

Scores on an English test are normally distributed with a mean of 33.8 and a standard deviation of 8.5. Find the score that separates the top 59% from the bottom 41%

2nd dist. #3

AREA: .41

U: 33.8 δ: 8.5

= .31.865

9. find the indicated Probability.

The diameters of bolts produced by a certain machine are normally distributed with a mean of 0.30 inches and a standard deviation of 0.01 inches. What percentage of bolts will have a diameter greater than 0.32 inches?

P(x>.32)

2nd dist. #2

LOWER: .32

UPPER: 999999

U: .30 δ: .01

= .022750062 =.0228 MOVE DECIMAL TO THE RIGHT 2 PLACES TO GET THE PERCENTAGE 2.28%

SOLVE THE PROBLEM

10. the amount of snow