One-third of the fish in liam's fish tank were added today. half of the other fish were a gift to liam last week. the other 9 came from liam's old fish tank. how many fish are in the tank? what is the difference between the number of fish liam had in his old tank and the number he has now?

There are 54 fish in the tank. The difference between the fish he had and the fish he has now is 45 fish. 1/3=2/6 1/2=3/6. I converted so there is a common denominator. 2/6+3/6=5/6. That leaves 9 fish. 9 fish is 1/6. So if I multiply 9 by 5 that gives me the rest of the fish, which is 45. Then, I add that together to get 54.