Answer:
1
Explanation:
The probability that a random variable has a particular value or a range of values is the sum of the probabilities associated with each of the values.
Application
All of the x-values in the table are less than or equal to 20, so p(x≤20) is the sum of all of the probabilities in the table.
p(x≤20) = 0.20 +0.15 +0.05 +0.1 +0.25 +0.1 +0.15 = 1.00
The probability is 1 that x ≤ 20.