Final answer:
The present value of the described perpetuity is $235,344.83, calculated by summing the annual payments and dividing by the effective annual interest rate of 11.6%.
Step-by-step explanation:
To calculate the present value of a perpetuity with variable payments, we would use the present value formula for perpetuities and adjust for the increased payment in the 12th month. The perpetuity pays $2,100 monthly for 11 months and then $4,200 (double the monthly payment) at the end of the 12th month each year.
First, we find the annual payment summing up all the monthly payouts: $2,100 * 11 months + $4,200 = $27,300. Next, we use the formula for the present value of a perpetuity PV = C / r, where C is the annual cash flow and r is the annual discount rate.
Since the annual effective rate is 11.6%, we have r = 0.116. Therefore, the present value of this perpetuity is PV = $27,300 / 0.116 = $235,344.83 (rounded to two decimal places).