If she bought 3 hot dogs for $1.59 each, then she spent $4.77 on the hot dogs. If she spend a total o $7.74 total, and she spent $4.77 on hot dogs, that means that she spent $2.97 on the fries. An equation for this would be 3x = 2.97. Divide both sides by 3 to solve for x, a single order of fries. x = .99
