The following describes the conditions of an ordinary annuity, with interest compounded with each payment and payments made at the end of the compounding period. Find the accumulated amount of the annuity. $1000 monthly payments at 7.9% for 10 years
This is a geometric sum where you start with a thousand dollars, multiply by 1.079, and do it 12*10=120 times.
So the sum is 1000*(1-1.079^120)/(1-1.079). Good luck!