please explain without excel, steps to find anwser

Your parents (or other wealthy people in your family) give you an allowance for some reason of $25 week. You have other ways of making money, but you still like receiving free money. So you decide to invest your allowance in an asset that pays a constant 10.4% interest. Your wealthy family members automate this at some point and accidentally forget about it, so your allowance payments will continue indefinitely until you tell them about it. You don't tell them about it. You continue to collect the $25/week until you retire 50 years from now. What size will your piggybank of unearned money grow to at the end of 50 years