Question

Question 8 From the employees of a company, 5 persons are selected to represent them in the managing committee of the company. Particulars of five persons are as follows:




S. No. Name Sex Age in years


1. Harish M 30


2. Rohan M 33


3. Sheetal F 46


4. Alis F 28


5. Salim M 41



A person is selected at random from this group to act as a spokesperson. What is the probability that the spokesperson will be either male or over 35 years?

Class X1 - Maths -Probability Page 409

Answer 1

concept : if selected person is either A or B
then, P(A U B ) = P( A ) + P( B ) - P( A ∩ B )

Let P( A ) is the Probability of number of male person
P ( B ) is the Probability of over 35 years .

P ( A ) = n ( A )/ n ( S ) = ³C₁ / ⁵C₁
={ 3!/2!} /{ 5!/4! }
= 3/5

P( B ) = n ( B )/n( S ) = ²C₁ / ⁵C₁
= { 2!/1!}/{5!/4!}
= 2/5

P ( A ∩ B ) means Probability of male and over 35 years . { you can see that only 1 person " Salim " is eligible }
P ( A ∩ B ) = n ( A ∩ B )/n ( S ) = 1/5

now,
P( A U B ) = P( A ) + P( B ) - P( A ∩ B )
= 3/5 + 2/5 - 1/5
= 4/5

Answer 2

I HOPE IT WILL HELP YOU.

THANK YOU.