Who is asking: Student
You can set this up as an algebraic equation and then solve the equation, but I think it is easier just to think about what it says. If you take a number, divide by 4 and get the answer 5, then the number must have been 20 since 5 times 4 is 20. Thus if you add n to 7 you get 20. What is n?
When you think you know what n is, check your answer. Add n to 7 and divide by 4. Do you get 5?Cheers,