wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

Statistics Normal Calculations

Total questions: 15

Worksheet time: 15mins

Name
Class
Date
1.

The weights of paper discarded each week by households are normally distributed with a mean of 9.43 pounds and a standard deviation of 4.17 pounds. The top 10% of households discard at least (a)   pounds of paper.

2.

The lengths of human pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. How long is a pregnancy if it is considered one of the top 20% in length?

a)

280 days or more

b)

255 days or more

c)

249 days or more

d)

287 days or more

3.

What is the the total area under the standard normal distribution curve?

a)

100

b)

25

c)

.5

d)

1

4.

What shape is a normal distribution curve?

a)

Half curve

b)

Round curve

c)

Bell curve

d)

Square curve

5.

What is the z-score for the mean?

a)

-1

b)

+1

c)

0

d)

It doesn't have one!

6.

If I have a positive z-score, I scored ABOVE or BELOW the mean?

a)

ABOVE

b)

BELOW

7.

The scoring of modern IQ is such that Intelligence Quotients (IQs) have a normal distribution of μ= 100 and 𝞂 = 15.


Mensa International is a non-profit organization that accepts only people with IQ score within the top 2%. What level of IQ qualifies one to be a member of Mensa?

a)

115

b)

131

c)

145

d)

120

8.

In a survey of men in the United States (ages 20-29), the mean height was 69.6 inches with a standard deviation of 3.0 inches. Find the minimum height in the top 22%.

a)

69.37 in 

b)

67.58 in 

c)

73.12 in 

9.

The distances male long jumpers for State College jump are approximately normal with a mean of 263 inches and a standard deviation of 14 inches.  
Suppose a male long jumper's jump ranked in the 75th percentile.  How long was his jump?

a)

0.67 inch

b)

263 inches

c)

272.44 inches

d)

277.25 inches

10.

A study of the amounts of time college freshmen study each week found that the times are normally distributed with a mean of 7.06 hours and a standard deviation of 2.32 hours. How many hours would the "fastest" 5% of students spend on homework?

a)

10.03 hours or less

b)

10.86 hours or less

c)

4.09 hours or less

d)

3.24 hours or less

11.

The lengths of human pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. 25% of pregnancies are under (a)   days in length. (Type the value only)

12.

The distances male long jumpers for State College jump are approximately normal with a mean of 263 inches and a standard deviation of 14 inches.  
What is the probability the next male long jumper from State College jumps longer than 270 inches?

a)

0.1888

b)

0.3085

c)

0.8035

d)

0.3585

13.

The distances male long jumpers for State College jump are approximately normal with a mean of 263 inches and a standard deviation of 14 inches.  
What is the standardized score of a male jumper from State College who jumped 280 inches?

a)

-1.21

b)

-1

c)

1

d)

1.21

14.

The distances male long jumpers for State College jump are approximately normal with a mean of 263 inches and a standard deviation of 14 inches.  
If a male long jumper from State College jumps 265 inches, what percentile does he fall in?

a)

56th

b)

57th

c)

67th

d)

79th

15.

The distances male long jumpers for State College jump are approximately normal with a mean of 263 inches and a standard deviation of 14 inches. 
If a male long jumper from State College jumps 270 inches, what percent of male long jumpers jumped further than him?

a)

31%

b)

39%

c)

69%

d)

70%