Question

In a certain class of​ students, there are 11 boys from​ Wilmette, 7 girls from​ Wilmette, 5 boys from​ Winnetka, 4 girls from​ Winnetka, 4 boys from​ Glencoe, and 4 girls from Glencoe. If the teacher calls upon a student to answer a​ question, what is the probability that the student will be a​ boy

Answer 1

Answer:

9/24

Step-by-step explanation:

Answer 2

Answer:

Probability that a boy will answer the question = $\frac{4}{7}$

Step-by-step explanation:

In a certain class of students,

Number of boys from Wilmette = 11

Number of boys from Winnetka = 5

Number of boys from Glencoe = 4

Total boys in the class = 11 + 5 + 4 = 20

Similarly, total number of girls in the class = 7 + 4 + 4 = 15

Total number of students in the class = 20 + 15 = 35

Now number of ways we can choose 1 boy out 20 boys

= $^{20}C_{1}=20$

Similarly number of ways, we can choose a boy out of 35 students = $^{35}C_{1}=35$

Now the probability that a boy will answer the question = $\frac{20}{35}$

= $\frac{4}{7}$