Question

Hello, can someone help with this problem?

The graph shows the probability distribution of a random variable.
What is the value of P(4≤X≤8)?

0.40
0.45
0.50
0.55

Answer 1

The correct answer is 0.55

Answer 2

P(5 ≤ X ≤ 8) = a rectangle with a width of 3 and height of .15 = 3(.15) = .45

P( 4 ≤ X ≤ 5) = a triangle with a base of 1 and a height of (0.15 -0.05) = .10

So....this area = (1/2)(1)(.10) = .05

And another rectangle with a width of 1 and height of .05 = (1) (.05) = .05

So

Adding these areas

P( 4 ≤ X ≤ 8 ) = .45 + .05 + .05 = .55

Explanation:

Hoped this helped!