Arestaurant has one type of lemonade that is 12% sugar and another that is 7% sugar. how many gallons of each type does the restaurant need to make 20 gallons of a lemonade mixture that is 10% sugar?
a) 12 gallons of the 12%, and 8 gallons of the 7%
b) 10 gallons of the 12% and 10 gallons of the 7%
c) 8 gallons of the 12% and 12 gallons of the 7%
d) 2 gallons of the 12% ad 18 gallons of the 7%