Question

Let x be the number of points that can be scored on 1 question of a statistics exam. Below is the probability distribution of how students did. x 0 1 2 3 P(x ) 0.13 0.21 0.55 0.11 Find the probability that x is at most 2.

Answer 1

Answer: The probability that x is at most 2 = 0.89

Step-by-step explanation:

Let x be the number of points that can be scored on 1 question of a statistics exam.

Given table: x       0          1           2           3

                P(x) 0.13   0.21     0.55         0.11

$P(X\leq2)=P(X=0)+P(X=1)+P(X=2)\\\\P(X\leq2)= 0.13+0.21+0.55\\\\P(X\leq2)= 0.89$

Hence, the probability that x is at most 2 = 0.89