How do you find this question i work on it but it does not make any sense

Hello there! 

The first step in solving this problem is to identify the number being used so you know what equation to use. 
The square root of 49 is 7 (7*7=49). Since 7 is an odd number, you would use the equation f(x)=2x-1. I've graphed 2x-1 below. 

Hope this helps! 
-Astro, Helper-In-Training 

Step-by-step explanation:

Lets understand the question.

Liam had $250

Cost of gift = p

Total Students = 24 (including Liam)

Each paid:

p/24 (Liam also paid this amount)

So, in terms of Liam, he would have:

250 (already had)

expended p/24 for gift, now he has:

This is amount of money Liam had left in terms of p.