Last month, a dwarf lemon tree grew half as much as a semi dwarf lemon tree. a full size lemon tree grew three times as much as the semi dwarf lemon tree. together, the three trees grew 27 inches.

Using a simple guess and check method, i started with the lowest common multiple of 3, and 27 (the total growth) and used 3. if you plug i the numbers, we will say a is the dwarf lemon tree, b is the semi-dwarf lemon tree, and c is the full lemon tree, you know 3times2 equals 6. if you triple 6 you get 18. so if A grew 3 inches , B had to have grown 6 inches, and C had to have grown 18 inches. add them all and you get 27. so the dwarf lemon tree grew 3 inches, semi dwarf grew 6 inches, the full size grew 18 inches.