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,69n,693n respectively. What is the number of people who like facebook?
The correct option is C72 Since, the number of people cannot be fraction, the values of n and 3n need to be factors of 69. ∴n can be only 1 (or) 23 ∴ No. of people who like facebook =3n+69n=72