IBPS PO Exam 2014 Solved Paper

Let S be the sample space and E be the event of selecting 1 girl and 2 boys.
Then, n(S) = Number ways of selecting 3 students out of 25
=

25

‌

C3
=

(25×24×23)

(3×2×1)

= 2300
n (E) = (

10

‌

C1×

15

‌

C2)
= [10×

(15×14)

(2×1)

] = 1050.
∴ P(E) =

n(E)

n(S)

=

1050

2300

=

21

46