Question

At a certain college, 30% of the students major in engineering, 20% play club sports, and 10% both major in engineering and play club sports. A student is selected at random. What is the probability that the student is majoring in engineering?

Answer 1

The probability that a student selected at random majors in engineering is 30% which is 0.3.

The probability  that the student both majors in engineering and play club sports is 10% which is 0.1.

For a student who is selected at random to be one who majors in engineering, there are two possible ways.

The student majors in engineering OR the Student both majors in engineering and plays club

The Probabilty that the student majors in Enginnering =

The probability that the student majors in engineering plus the  probability that Student both majors in engineering and plays club sport

= 0.3+0.1= 0.4