Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Probability

Question:

The random variable X has a probability distribution P(X) of the following form, where k is some number.

$P(X=x)\left\{\begin{array}{clc} k, & \text { if } ~~x=0 \\ 2 k, & \text { if } ~~x=1 \\ 3 k, & \text { if } ~~x=2 \\ 0, & \text { otherwise } \end{array}\right.$

Then P(x ≤ 2) is:

Options:

0

1

$\frac{1}{6}$

$\frac{1}{2}$

Correct Answer:

1

Explanation:

The correct answer is Option (2) - 1

$∑P(X=1)⇒k+2k+3k+....$

$=6k=1⇒k=\frac{1}{6}$

$P(X≤2)=6k=1$