Question

In a survey it was found that, the number of people who like only What’s app, only Facebook, both What’s app and Facebook and neither of them are $2n,3n,\frac{69}{n},\frac{69}{3n}$
respectively. What is the number of people who like facebook?

• A. $49$
• B. $36$
• C. $72$
• D. $23$

Answer 1

The correct option is C $72$

Since, the number of people cannot be fraction, the values of $n$ and $3n$ need to be factors of $69.$
$\therefore n$ can be only $1$ (or) $23$
$\therefore$ No. of people who like facebook $=3n+\frac{69}{n}=72$