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

NUMERICAL
Let X = {n $ \in $ N : 1 $ \le $ n $ \le $ 50}. If A = {n $ \in $ X: n is a multiple of 2} and B = {n $ \in $ X: n is a multiple of 7}, then the number of elements in the smallest subset of X containing both A and B is ________.
MCQ_SINGLE
Let $X = {1, 2, 3, 4, 5}$. The number of different ordered pairs $(Y, Z)$ that can be formed such that $Y \subseteq X$, $Z \subseteq X$ and $Y \cap Z$ is empty, is:
MCQ_SINGLE
Let $A = { (\alpha, \beta ) \in R \times R : |\alpha - 1| \leq 4$ and $|\beta - 5| \leq 6 }$ and $B = { (\alpha, \beta ) \in R \times R : 16(\alpha - 2)^{2}+ 9(\beta - 6)^{2} \leq 144 }$. Then
MCQ_SINGLE
Let $A = {2, 3, 4, 5, ....., 30}$ and '$\simeq$' be an equivalence relation on $A \times A$, defined by $(a, b) \simeq (c, d)$, if and only if $ad = bc$. Then the number of ordered pairs which satisfy this equivalence relation with ordered pair $(4, 3)$ is equal to :
MCQ_SINGLE
For $\alpha \in N$, consider a relation $R$ on $N$ given by $R = \{(x, y) : 3x + \alpha y$ is a multiple of $7\}$. The relation $R$ is an equivalence relation if and only if :
View All Questions