Help me this is so hard

If the class was going to get a class pet and 5 picked fish and 7 pick bird and 8 picked rabbits have many students were in the

Draw a tape diagram to represent each situation.for some of the situations,you need to decide what to represent with a variable andre bakes 9 pans of brownies.he donates 7 pans to the school bake sale and keeps the rest to divide equally among his class of 30 students

Math i have no idea how to do a and b