Since 1 US Dollar is equal to 7.84975 Hong Kong Dollars, we could say that n United States Dollars are equal to 7.84975 times n Hong Kong Dollars. In other words, we could use the following formula:
Hong Kong Dollars = United States Dollars x 7.84975
For example, let's say that we want to convert 2 United States Dollars to Hong Kong Dollars. Then, we just replace United States Dollars in the abovementioned formula with 2:
Hong Kong Dollars = 2 x 7.84975
That is, 2 United States Dollars are equal to 15.6995 Hong Kong Dollars.