Ordinary Annuity an PMT = PV decreasing monthly paymenty dec a) PmT paying off Glebt (balance decreas03 [ m 1+m) 18. a. A company buys a copy machine for $12,000. It amortizes the cost at 12% monthly over 5 years. How much are the monthly payments? b. At the time they retire, a couple wishes to establish an account that pays 8.4% from which they can withdraw $2000 monthly for 20 years. How much should they invest in this account? rmt m 11.000-mt A = R present .12 12 1- increasing PV = PMT 1+ () Imi annual payment. nor - m) 1- (1+-+2) - 12 (5) b) $2000 x 20 x 12 = 480,000 needed G-mt m 111, 222.24 19. a. You deposit $3000 each year into a retirement account that earns 5% compounded continuously. How much will you have at the end of 40 years? A shop owner deposits the income from her florist shop at the rate of flow given by