question_answer

In a certain town, 25% families own a cell phone, 15% families own a scooter and 65% families own neither a cell phone nor a scooter. If 1500 families own both a cell phone and a scooter, then the total number of families in the town is

A) 10000                   

B) 20000

C) 30000                   

D) None of these

Correct Answer: C

Solution :

Let the total population of town be \[x\] \[\therefore \]  \[\frac{25x}{100}+\frac{15x}{100}-1500+\frac{65x}{100}=x\] \[\Rightarrow \]                               \[\frac{105x}{100}-x=1500\] \[\Rightarrow \]               \[\frac{5x}{100}=1500\Rightarrow x=3000\]