USD/HKD = (121.4015.70)/(121.6015.60) = 7.7325/7.
Determine the exchange rate again
The bank quotation is the price of buying the benchmark currency (in this case, the US dollar) and the price of selling the benchmark currency. In this case, the customer sells the benchmark currency USD, that is, the bank buys the benchmark currency, and the purchase price is 7.7325.