Question

x	0	1	2	3	4	5
P(X ≤ x)	0.18	0.35	0.47	0.73	0.88	1

a. Calculate P(X ≤ 1). (Round your answer to 2 decimal places.)

b. Calculate P(X = 3). (Round your answer to 2 decimal places.)

c. Calculate P(1 ≤ X ≤ 3). (Round your answer to 2 decimal places.)

Answer 1

a)

P(X < 1) 0.35

We get directly from given tables.

b)

$P(X=3)=P(X\leq 3)-P(X\leq 2)$

We can get above cumulative probabilities from given table. So,

P(X = 3) = 0.73-0.47 = 0.26

c)

$P(1\leq X\leq 3)=P(X\leq 3)-P(X\leq 0)$

We can get above cumulative probabilities from given table. So,

P(I < X < 3) 0.73-0.18-0.55