An investment paid to you in one year in the amount of $100 will be worth how much today

use FV = PV (1+ i)^N and the answer is 85
use PV = FV/(1+r) and the answer is about 90.91
use FV = PV(1 + i)^N and the answer is 90
use PV =FV(1+r) and the answer is about 109.91