Question

A math teacher randomly selects one student in a class to write a probability question on a chalkboard. The teacher then randomly selects a different student to answer the probability question. There are 12 boys in the class, and the ratio of boys to girls is 2:3. Find the probability that the teacher selects a girl first and a girl second. Write your answer as a decimal rounded to the nearest thousandth.

Answer 1

The Probability that she does is 51/145 or 35%. I hope i am right and was able to help.

Answer 2

Answer:

The probability that the teacher selects a girl first and a girl second is 0.352

Step-by-step explanation:

Number of boys in class = 12

let number of boys in class = 2x

number of girls in class = 3x

According to the question,

2x = 12

x = 6

So, number of girls = 3x = 3 × 6 = 18

Total number of students = 18 + 12 = 30

$Probabiltiy=\frac{Number\:of\:favorable\:outcome}{Number\:of\:Total\:outcome}$

Probability of selecting a girl first and second girl = $\frac{18}{30}\times\frac{17}{29}$

$=\frac{51}{145}=0.352\:(nearest\:thousandth)$

Therefore, The probability that the teacher selects a girl first and a girl second is 0.352