Brian and leo are purchasing food at the snack bar. Brian purchases a hot dog for $2.35, chips for $1.65 and a drink for $2. Leo purchased a hamburger for $3, fries for $2.45 and a drink for $2. How much did they spend altogether on food?

The volume of gas a balloon can hold varies directly as the cube of its radius. imagine a balloon with a radius of 3 inches can hold 81 cubic inches of gas. how many cubic inches of gas must be released to reduce the radius down to 2 inches?