Use a rational equation to solve: in the aquarium, 90% of the fish are blue. the rest of the fish are red. the blue fish number 10 more than twice the number of red fish.

Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.