Question

A school has five houses A, B, C, D and E. A class has 23 students, 4 from house A, 8. from house B, 5 from house C, 2 from house 0 and rest from house E. A single student is selected at random ,to be the class monitor. The probability that the selected student is not from A, Band C is?

• A. $\frac{4}{23}$
• B. $\frac{6}{23}$
• C. $\frac{8}{23}$
• D. $\frac{17}{23}$

Answer 1

The correct option is B $\frac{6}{23}$

Total number of students, n(S) = 23

Number of students in houses A,B and C

= 4+8+5 = 17

∴ Remaining students = 23 - 17 = 6 n(E) = 6

So, probability that the selected students is not from A,B and C

$P\left(E\right)=\frac{6}{23}$