21 - A whale is 15 meters long. Its head is the same size as its tail. If the head were twice its actual size, the head and tail together would have the same length as the rest of the whale's body. What are the lengths of the head, tail, and the rest of the body? Separate answers with commas. Example: 'X, Y, Z' (X meters for head, Y meters for tail, and Z meters for the rest of the body)
Answer
3, 3, 9