How much will you need to invest each month over the next 30 years in order to meet your savings goal of $750,000, assuming you average a 7% real rate of return each year?

Rate = 7% / 12 = 0.5833% (monthly)

Savings goal, FV = $750,000

Number of periods = 30 * 12 = 360

Future value = Monthly payments * [ (1 + r) ^n - 1] / r

750,000 = Monthly payments * [ (1 + 0.005833) ^360 - 1] / 0.005833

750,000 = Monthly payments * 1,219.874713

Monthly payments = $614.82