UTS Information Economics

Haris sell T-Shirt. And Haris has an opportunity to receive Rp.450.000 one month from now. If he can earn 15% on his sale in the normal course of events, what is the most he should pay now for this opportunity?
We can know :

FV1 = Rp.450.000, n = 1 and i = 0,15
PV = FVn/(1+i)n
Answer :
PV = Rp.450.000/(1+ 0,15)
= Rp.517.500
The value today (“present value”) of Rp.450.000 received one month from today, given an opportunity cost of 15% is Rp.517.500 .