13) suppose that computer literacy among people ages 40 and older is being studied and that the accompanying…

13) suppose that computer literacy among people ages 40 and older is being studied and that the accompanying tables describes the probability distribution for four randomly selected people, where x is the number that are computer literate. is it unusual to find four computer literates among four randomly selected people? a) yes \n0 1 2 3 4\np(x) 0.16 0.25 0.36 0.15 0.08\nb) no
Answer
Explanation:
Step1: Recall the criteria for a probability distribution
A probability distribution must satisfy two conditions: 1. (0\leq P(x)\leq1) for all (x), and 2. (\sum_{x}P(x) = 1).
Step2: Check the sum of probabilities
(\sum_{x = 0}^{4}P(x)=0.16 + 0.25+0.36 + 0.15+0.08) [ \begin{align*} &0.16+0.25 + 0.36+0.15+0.08\ =&(0.16 + 0.25)+0.36+(0.15 + 0.08)\ =&0.41+0.36 + 0.23\ =&0.77+0.23\ =&1 \end{align*} ] Also, (0\leq0.16\leq1), (0\leq0.25\leq1), (0\leq0.36\leq1), (0\leq0.15\leq1) and (0\leq0.08\leq1). So it is a valid probability - distribution.
Step3: Check for unusualness
An event is considered unusual if its probability is less than or equal to (0.05). The probability of having four computer - literates (P(x = 4)=0.08>0.05). So it is not unusual.
Answer:
B. No