Class JEE Mathematics Sets, Relations, and Functions Q #1061
KNOWLEDGE BASED
APPLY
4 Marks 2019 JEE Main 2019 (Online) 9th April Evening Slot MCQ SINGLE
Two newspapers A and B are published in a city. It is known that $25$% of the city populations reads A and $20$% reads B while $8$% reads both A and B. Further, $30$% of those who read A but not B look into advertisements and $40$% of those who read B but not A also look into advertisements, while $50$% of those who read both A and B look into advertisements. Then the percentage of the population who look into advertisement is :-
(A) $13.5$
(B) $13$
(C) $12.8$
(D) $13.9$
Prev Next
Correct Answer: D
Explanation
Let the total population be $100$. Then:

People who read A only: $25 - 8 = 17$

People who read B only: $20 - 8 = 12$

People who read A and look into advertisements: $0.30 \times 17 = 5.1$

People who read B and look into advertisements: $0.40 \times 12 = 4.8$

People who read both A and B and look into advertisements: $0.50 \times 8 = 4$

Total percentage of people who look into advertisements: $5.1 + 4.8 + 4 = 13.9$

Therefore, the percentage of the population who look into advertisement is $13.9$%.

More from this Chapter

MCQ_SINGLE
Among the relations $S = {(a, b) : a, b \in R - {0}, 2 + \frac{a}{b} > 0}$ and $T = {(a, b) : a, b \in R, a^2 - b^2 \in Z}$,
NUMERICAL
The number of relations on the set $A=\{1,2,3\}$, containing at most 6 elements including $(1,2)$, which are reflexive and transitive but not symmetric, is __________.
MCQ_SINGLE
Let $A = {1, 3, 4, 6, 9}$ and $B = {2, 4, 5, 8, 10}$. Let $R$ be a relation defined on $A \times B$ such that $R = {((a_1, b_1), (a_2, b_2)): a_1 \le b_2 \text{ and } b_1 \le a_2}$. Then the number of elements in the set R is :
MCQ_SINGLE
Which of the following is not correct for relation $R$ on the set of real numbers?
NUMERICAL
Let $A=\{1,2,3,4,5,6,7\}$. Define $B=\{T \subseteq A$ : either $1 \notin T$ or $2 \in T\}$ and $C=\{T \subseteq A: T$ the sum of all the elements of $T$ is a prime number $\}$. Then the number of elements in the set $B \cup C$ is ________________.
View All Questions