The present value of a given sum to be received in five years will be exactly twice as
great as the present value of an equal sum to be received in ten years.

The present value of a sum to be received in five years is not exactly twice as great as the present value of an equal sum to be received in ten years, especially when considering a discount rate of 16%. The present value decreases as the time frame extends, due to the time value of money, but the relationship is not a simple doubling when moving from five to ten years, particularly at a specific discount rate like 16%.