Question

Suppose the length of time cats sleep each day is normally distributed with a mean of 15 hours and a standard deviation of 2 hours.

Which group describes 16% of the cat population?

Select each correct answer.

cats that sleep more than 19 hours a day

cats that sleep less than 11 hours a day

cats that sleep less than 13 hours a day

cats that sleep more than 17 hours a day

Answer 1

@Vocaloid

Answer 2

16% of the data lies EITHER one sd above the mean or one sd below the mean

Answer 3

calculate:

mean + one standard deviation
mean - one standard deviation

let me know when you are done

Answer 4

thats the thing, im not that good with this stuff

Answer 5

the mean is 15
the standard deviation is 2

Answer 6

mean + one standard deviation = ___
mean - one standard deviation = ___

fill in the blanks

Answer 7

17 and 13

Answer 8

good so your answer should be: cats that sleep more than 17 and cats that sleep less than 13 hours

Answer 9

The weights of bags of ready-to-eat salad are normally distributed with a mean of 300 grams and a standard deviation of 9 grams.

What percent of the bags weigh less than 291 grams?



13.5%

16%

34%

36.5%

Answer 10

nvm, its 16%

Answer 11

good

Answer 12

The number of unshelled peanuts in a 1 lb container is normally distributed with a mean of 375 peanuts and a standard deviation of 24 peanuts.

Suppose 4000 different 1 lb containers are in a warehouse.

About how many containers contain more than 447 peanuts?



6

12

100

200

Answer 13

hint: how many standard deviations above the mean is 447?

Answer 14

24

Answer 15

nope, I said how MANY standard deviations, not what the standard deviation is

Answer 16

mean + __ * standard deviation = 447

fill in the blank

Answer 17

12?

Answer 18

375 + __ * 24 = 447

fill in the blank

Answer 19

6?

Answer 20

447 - 375 = ?

Answer 21

72

Answer 22

good, and 72/24 = ?

Answer 23

-1118?

Answer 24

/ means divide

Answer 25

72 divided by 24 is...?

Answer 26

3

Answer 27

good, so that means we are 3 standard deviations above the mean, which represents 0.015% of the data

Answer 28

0.015% of 4000 is?

Answer 29

0.6

Answer 30

oh whoops I think I made a decimal error

Answer 31

should be 0.15% of 4000 = 6 = your answer

Answer 32

Times for an ambulance to respond to a medical emergency in a certain town are normally distributed with a mean of 450 seconds and a standard deviation of 50 seconds.

Suppose there are 97 emergencies in that town.

In about how many emergencies are the response times expected between 400 seconds and 500 seconds?



31

33

47

66

Answer 33

hint: 400 is ___ standard deviations below the mean

fill in the blank

Answer 34

is the?

Answer 35

what?

Answer 36

you should fill in the blank with a number

Answer 37

i dont get this hint, you want me to say "the"?

Answer 38

there should be a number inside the blank

Answer 39

if the standard deviation is 50 and the mean is 450

then how many standard deviations is 400 below the mean?

Answer 40

400 = 450 - ___ * 50

fill in the blank with a number

Answer 41

31?

Answer 42

subtract 450 from both sides

Answer 43

i got 47

Answer 44

-50 = ___ * 50

fill in the blank with the appropriate number

Answer 45

what number can we multiply with 50 to get -50?

Answer 46

still there?

Answer 47

Nah.