Answer
P (x ≤ 20) = 1.00
Step-by-step explanation
We are given the probability distribution for a random variable x that ranges from -10 to 20, in steps of 5.
We are then told to calculate the probability that x ≤ 20.
Note that this stands for the probability that x is less than or equal to 20.
P (x ≤ 20) = P(x=20) + P(x=15) + P(x=10) + P(x=5) + P(x=0) + P(x=-5) + P(x=-10)
= 0.15 + 0.10 + 0.25 + 0.10 + 0.05 + 0.15 + 0.20 (These numbers are given in the table)
= 1.00
Hence, P (x ≤ 20) = 1.00
Hope this Helps!!!