retagged by
2,279 views
3 votes
3 votes

A gathering of $50$ linguists discovered that $4$ knew Kannada$,$ Telugu and Tamil$,$ $7$ knew only Telugu and Tamil $,$ $5$ knew only Kannada and Tamil $,$ $6$ knew only Telugu and Kannada$.$ If the number of linguists who knew Tamil is $24$ and those who knew Kannada is also $24,$ how many linguists knew only Telugu$?$

  1. $9$
  2. $10$
  3. $11$
  4. $8$ 
retagged by

2 Answers

Best answer
6 votes
6 votes
Let  $K_a$ denote Kannada, $T_a$ denote Tamil and $T_e$ denote Telegu.

$n(K_a \cup T_a \cup T_e ) = n(K_a) + n(T_a) + n(T_e) - n(K_a \cap T_a ) - n(K_a \cap T_e ) - n(T_e \cap T_a ) + n(K_a \cap T_a \cap T_e )$

$\implies  50 = 24 +24 + n(T_e) - (5+4) - (6+4) - (7+4) + 4$

$\implies  50 = 48 + n(T_e) - 26$

$\implies n(T_e)  = 28.$

$\therefore$ Number of people who know Telegu, $n(T_e) =28.$

Number of people who know only Telegu

$= n(T_e) - n(K_a \cap T_e ) - n(T_e \cap T_a ) + n(K_a \cap T_a \cap T_e )$

$= 28 -(6+4) -(7+4) +4$

$= 11$

Correct Option: C.
7 votes
7 votes

Here the ONLY word used in question is important.

$\therefore$ Option $C.$ is correct.

edited by
Answer:

Related questions

4 votes
4 votes
3 answers
3
admin asked May 13, 2019
1,124 views
Consider the series $\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+\frac{1}{8}+\frac{1}{9}-\frac{1}{16}+\frac{1}{32}+\frac{1}{27}-\frac{1}{64}+\ldots.$ The sum of the infinite seri...
8 votes
8 votes
3 answers
4
admin asked May 13, 2019
1,386 views
Consider the function $f(x)=\max(7-x,x+3).$ In which range does $f$ take its minimum value$?$ $-6\leq x<-2$ $-2\leq x<2$ $2\leq x<6$$6\leq x<10$