16. Standard Normal Distribution

Question 1

The lifespans of lions in a particular zoo are normally distributed. The average lion lives 12.5 years; the standard deviation is 2.4 years.
What is the probability the lion lives less than 10.1 years?

A) 32%
B) 10%
C) 16%
D) 18 %

MM

Answer 1

Answer = C

Question 2

Decreasing the sample size will increase your confidence interval. True or false?

A) T
B) F
C) No

MM

Answer 2

Answer A

b/c to calculate confidence interval the Standard error of mean in in there its something like CI= XZSEM

SEM = sd/sqr root of sample
so dec sample = inc SEM = ^ CI interval

Question 3

Choose all of the required information in order to calculate a z-score (MG)

A. Mean
B. Standard deviation
C. Median
D. IQR

Answer 3

A. Mean
B. Standard deviation

And the data set has to be normally distributed

Question 4

Assume that hours spent binging Netflix in the SGU student population is normally distributed, with a mean of 6 hours per week, with a standard distribution of 3 hours. You binge 8 hours per week. How many standard deviations are you above the mean? (MG)

A. 0.67
B. 0.33
C. 1
D. 0.75

Answer 4

A. 0.67

(8-6)/3 =

Z = 0.67

Question 5

A study examines the amount of times Term 3 SGU students visit the gym weekly. The mean for 400 students is 2 times per a week with a standard deviation of 2. Calculate the 95% confidence interval for this population.

A.  2 ± 1.96
B. 2 ± 3.0
C. 2 ± 0.2
D. 2 ± 0.5
E. 2 ± 0.75

SZ

Answer 5

Ans C

Z scored for 95% confidence interval is 1.96.

Standard errror mean = 2/ (square root of 400) = 0.1.
2 ± (1.96)(0.1)
= 2 ± 0.2

Question 6

Which of the statements below best describes standard error?

A. Measure the variability of estimated population
B. Measure the variability of population around the mean
C. Does not increase or decrease with population size
D. Decreases as sample size increases
E. Both A & D
F. Both B & C

SZ

Answer 6

Ans. E.

Choices B and C describe standard deviation.

Question 7

What is the probability of rolling a 2 or a 4 on a six sided die?

A. 10%
B.2.8%
C.25%
D. 15.7%
E. 33.3 %

RFA

This is DLA Stuff

Answer 7

Ans E.

1/6+ 1/6= 33.#

Question 8

Adam loves Oreos there is a 77% probability that he will eat them on any day. Adam also loves getting his bell touched there is a 58% chance of happening any day. What is the probability that both of these independent events will happen on the same day.

A. 52.33%
B. 72.4%
C. 44.66%
D. 37.5%
E.135%

RFA

Answer 8

Ans C. 44.66%

.77% x .58%= 44.66 percent