Original practice · fully worked
Original variant: declining-date mural installments
A mural cooperative pays an artist 5 at month 1, 10 at month 2, and continues increasing each monthly installment by 5 through month 12. Money is valued at 0.5% per month. Determine the contract's present value.
- A
330.00 - B
350.00 - C
374.16 - D
390.00 - E
420.00
Answer and calculation
Five times the 12-payment increasing-annuity value is 374.16, choice C.
Setup
Setup
Month k carries payment 5k, so the contract is a scaled finite increasing annuity.
PV=5k=1∑12kvk,v=1/1.005 Model
Model
Discount each installment by k months at the monthly rate rather than using an annual factor.
PV=5(Ia)12∣0.005 Compute
Compute
The 12-term time-weighted discount sum multiplied by five equals 374.16265.
PV=374.16265 Answer
Answer
Thus the contract is worth 374.16 today, which is choice C.
PV=374.16(C)