In Exercises 7.62–7.63, was there something special about the number 3? Suppose that, due to geopolitical turmoil and a skyrocketing of the price of wool, the 5NZD bill is now worth b USDs, for some b...

In Exercises 7.62–7.63, was there something special about the number 3? Suppose that, due to geopolitical turmoil and a skyrocketing of the price of wool, the 5NZD bill is now worth b USDs, for some b ≡5 3. I still have many 5USD bills, and Nikki still has the equivalent of many b USD bills. What amounts can Nikki now pay me? Prove your answer

Exercises 7.62

Prove that Nikki can pay me exactly 4USD in value, through only the exchange of 5NZD and 5USD bills