. The random variable x is known to be uniformly distributed between 20 and 30. The probability of x having a value between 25 and 35 is.

a. 0.5

b. 0.05

c. 1

d. 0.75

3. The assembly time for a product is uniformly distributed between 9 and 11 minutes. The probability density function has what value in the interval between 9 and 11?

a. 2.00

b. 3.00

c. 0.50

d. 0

4. The assembly time for a product is uniformly distributed between 6 and 10 minutes. The probability of assembling the product in less than 6 minutes is.

a. .15

b. 1

c. .50

d. 0

5. The assembly time for a product is uniformly distributed between 6 and 10 minutes. The probability of assembling the product in 7 minutes or more is.

a. 0

b. 1

c. .25

d. .75

6. Assume z is a standard normal random variable. Then P(1.20 z 1.85) equals

a. .3849

b. .4678

c. .8527

d. .0829

7. Assume z is a standard normal random variable. Then P(1.10 z 1.65) equals

a. 0.3149

b. 0.8149

c. 0.9138

d. 0.0862

8. Assume z is a standard normal random variable. Then P(z 2.11) equals

a. .0174

b. .5

c. .9821

d. .4821

9. Given that z is a standard normal random variable, what is the value of z if the area to the right of z is 0.0571?

a. 1.58

b. 0.4773

c. -1.58

d. 1.90

10. For a standard normal distribution, the probability of obtaining a z value between -2.8 and -2.0 is

a. 0.0253

b. 0.0455

c. 0.0202

d. 0.0051