What is the decimal of that problem

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

Write the expression as a single natural logarithm. 2 in a - 4 in y

Another type of subtraction equation is 16-b=7. explain how you would sole this equation then solve it.