Currency derivatives are used by Rolls-Royce to hedge against exchange rate movements that may affect its proceeds in non-sterling currencies. Suppose Rolls-Royce signed a contract to supply engines for Boeing for the next five years. Boeing agrees to pay a sum of $680 million in year 4 of this agreement.

At the time of this agreement in May 2016, the exchange rate was £0.7739/$. When this payment was received in May 2020, the exchange rate was £0.81746/$. How much of this payment will be worth in pound sterling for Rolls-Royce at the time of signing the agreement in 2016? What will it be worth at the time of receipt in 2020?