Given the tables of probabilities for the random variable x

Given the tables of probabilities for the random variable x, do these form a probability distribution? Give a reason for your answer

x

0

1

2

3

4

P (x)

0.02

0.07

0.22

0.27

0.42

x

5

10

15

20

P (x)

0.10

- 0.30

0.50

0.70

Solution

Solution:

Since sum of probabilities =1

x 0 1 2 3 4

P(X):0.02+0.07+0.22+0.27+0.42=1

these form a probability distribution

Since the sum of probabilities=1

that is

X: 5 10 15 20

P(x)0.10+(-0.30)+0.50+0.70=1

these form a probability distribution