Question

A psychology test has personality questions numbered 1, 2, 3, intelligence questions numbered 1, 2, 3, 4, and attitudequestions numbered 1,2. If a single question is picked at random, what is the probability that the question is an intelligence question OR has an odd number?

Answer 1

7/9.

Step-by-step explanation?

Total number of questions: 3 + 4 + 2 = 9.

Number of Intelligence questions: 4

Number of questions that have an odd number: 5

The probability of a question is Intelligence questions = 4/9

The probability a question has an odd number = 5/9

The probability a question is Intelligence questions and has an odd number = 2/9

The probability a question is Intelligence question OR has an odd number is:

4/9 + 5/9 - 2/9 = 7/9.