The sum of all probabilities in a probability model must be equal to 1. Therefore, to find the value of x, we need to add all the probabilities given and subtract from 1.
0.30 + 0.25 + 0.20 + 0.15 + x = 1
0.90 + x = 1
x = 1 - 0.90
x = 0.10
Therefore, the value of x is 0.10.
If the table below represent a probability model based on observed frequencies, what is the value of x?
X B E A R S
P(X) 0.30 0.25 0.20 0.15 x
0.05
0.10
0.01
0.50
1 answer