Question

A few friends went to a restaurant and had to pay a bill of ₹ 500. If two of them didn't pay their share then each of them had to pay ₹12.50 more to make up the deficit. How many friends were there?

• A. 10
• B. 11
• C. 9
• D. 15

Answer 1

The correct option is A 10

Let the number of friends be x
Amount paid by each friend = Rs.$\frac{500}{x}$
Amount paid by each friend when two friends didn't pay = Rs.$\frac{500}{x-2}$
According to the question
$\frac{500}{x-2}-\frac{500}{x}=12.50$
$\Rightarrow 500x-500x+1000=12.50x(x-2)$
$\Rightarrow x^2-2x-80=0$
$\Rightarrow x^2-10x+8x-80=0$
$\Rightarrow (x-10)(x+8)=0$
Neglecting negative value,
$\Rightarrow x=10$
Hence, there were 10 friends.

So, option a is correct.