Expressing parametric equations that don't have an x or y equation

You eat 8 strawberries and your friend eats 12 strawberries from a bowl. there are 20 strawberries left. which equation and solution give the original number of strawberries?

Jackie purchased 3 bottles of water and 2 cups of coffee for the family for $7.35. ryan bought 4 bottles of water and 1 cup of coffee for his family for 7.15. how much does each bottle of water cost? how much does each cup of coffee cost?

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)