Question

In a class of students, the following data table summarizes how many

students have a brother or a sister. What is the probability that a
student chosen randomly from the class has a brother and a sister?

Answer 1

Step 1) Calculate total number of students in the class:

18 students with only a brother

+ 8 students with only a sister

+ 12 students with both a brother and sister

= 38 Total Students

Step 2) Calculate Probability

12 students with both a brother and sister

/ 38 Total Students

= 0.316 or 31.6%