Question

John is a 45 year old and wants to retire at age 65. He wishes to make monthly deposit into an account paying 9% compounded monthly so when he retires he can withdraw $320 a month for 30 years. How much should John deposit each month?

Answer 1

solve for x

x(1.0075^240 - 1)/.0075 = 320(1 - 1.0075^-360)/.0075
the denominators will cancel, so
x = 320*(1 - 1.0075^-360)/(1.0075^240 - 1)
= ...
you do the button pushing.
Let me know what you get