At a fundraiser , a sorority is able to raise $5 less than four times the amount of money a fraternity raises

All together they raised $115

First question what is known is the situation?

Second question what is unknown in the situation

Third question how do I write an equation that represents the situation use at to represent the fraternity

NEED HELP ASAP I WILL MARK YOU BRAINLIEST NO LINKS PLEASE AND THANK YOU