Spiro says "Choose a number. Add 5. Multiply by -4. subtract 3". For each starting number given, what is your ending number?

Someone . me. compound probability

Rob spent 25%, percent more time on his research project than he had planned. he spent an extra h hours on the project. which of the following expressions could represent the number of hours rob actually spent on the project? two answers

Math i have no idea how to do a and b