Elective Mathematics

Question 1

1For X ~ B(4, 0.5) the mean of X is ___

Easy

Your answer (fill in the blank)

Question 2

2For X ~ B(7, 0.2) the mean of X is ___

Easy

Your answer (fill in the blank)

Question 3

3The standard normal distribution has

Easy

A. mean 0 and standard deviation 1 B. mean 0 and sd 0 C. mean 1 and sd 1 D. mean 1 and sd 0

Question 4

4A fair-looking device succeeds with probability 0.2 each time. In 5 trials find P(exactly 2 successes) to 3 decimal places.

Hard

A. 0.04 B. 0.205 C. 0.305 D. 0.4

Question 5

5About what percentage of data lies within one standard deviation of the mean in a normal distribution?

Medium

A. 99% B. 95% C. 50% D. 68%

Question 6

6For X ~ B(5, 0.4), find the variance of X.

Medium

A. 1.2 B. 2 C. 0.24 D. 3

Question 7

7A negative z-score means the value is below the mean.

Easy

A. True B. False

Question 8

8A binomial distribution has independent trials.

Easy

A. True B. False

Question 9

9For X ~ B(6, 0.2) the mean of X is ___

Easy

Your answer (fill in the blank)

Question 10

10P(Z < 0) = 0.5 for the standard normal distribution.

Easy

A. True B. False