#25 plzz need a quick answer plzzz

You can find the constant of proportionality by finding the ratio of

If u good at math hit me up on insta or sum @basic_jaiden or @ and

Ineed big ! the cost of a school banquet is $25 plus $15 for each person attending. create a table, sketch the graph, and write an equation in slope-intercept and point-slope form that gives total cost as a function of the number of people attending. what is the cost for 77 people?