The proportion of students who own a cell phone on college campuses across the country has increased tremendously over the past few years. It is estimated that approximately 90% of students now own a cell phone. Fifteen students are to be selected at random from a large university. Assume that the proportion of students who own a cell phone at this university is the same as nationwide. Let X = the number of students in the sample of 15 who own a cell phone. 1. What is the appropriate distribution forX? **N = Normal, B = Binomial?
A. X is M(15, 0.9).
B, X is B(15, 09).
C. Xis B(15, 13.5).
D. Xis N(13,5, 1.16).
2. On average, how many students will own a cell phone in a simple random sample of 15 students?
a. 9.
b. 13
c. 13.5.
d. 14 17.
3. What is the standard deviation of the number of students who own a cell phone in a simple random sample of 15 students?
a. 0.077.
b. 0.09.
c. 1.16.
d. 1.35.
4. What is the probability that all students in a simple random sample of 15 students own a cell phone?
a. 0.
b. 0.1.
c. 0.206.
d. 0.9.