Suppose that about 85% of graduating students attend their graduation. A group of 22 graduating students is randomly chosen.
a. In words, define the random variable X.
b. List the values that X may take on.
c. Give the distribution of X. X ~ ___(_,___)
d. How many are expected to attend their graduation?
e. Find the probability that 17 or 18 attend.
f. Based on numerical values, would you be surprised if all 22 attended graduation? Justify your answer numerically

Question

Accepted Answer

a. The random variable X is the number of students that attended their graduation.

b. The values that X may take on are $0, 1, 2, . . . . ., 22 .$

c. The distribution $X ~ B (22, 0.85)$

d. $18.7$ are expected to attend the graduation.

e. The probability of $17 o r 18$ attend is $0.3249$

f. Yes, it will be surprising if all $22$ attended graduation as it is unusual.

Short Answer