Question: 15
(Choose 1 answer)
The random variable X represents the number of credit cards that adults have along with the corresponding
probabilities. Find the mean and standard deviation of X.
X P(X)
0 0.49
1 0.05
2 0.32
3 0.07
4 0.07
A. mean: 1.18; standard deviation: 1.30
B. mean: 1.39; standard deviation: 0.80
C. mean: 1.18; standard deviation: 0.64
D. mean: 1.39; standard deviation: 0.64
E. None of the other choices is correct
