Question

X:       0    1     2      3     4

p(x): 0.1 0.6 0.05 0.15 0.1

Geraldine surveyed her school to find the number of siblings that they had. She created a probability distribution which is displayed in the table. What is the average number of siblings for students in the school?

A) 1 sibling
B) 1.5 siblings
C) 2 siblings
D) 2.5 siblings

Answer 1

The answer you are looking for is 1.5 siblings.

Answer 2

The answer is B) 1.5
To find the expected number of siblings, multiply each outcome by the probability of the outcome (0)(0.1) + (1)(0.6) + (2)(0.05) + (3)(0.15) + (4)(0.1) = 1.55 OR 1.5 siblings.