If b is the length of the body, h is the length of the head, and t is the length of the tail, we know that b + h + t = 30, h = b/6 and t = b/2. We can substitute the second two equations into the first equation to get b + b/6 + b/2 = 30
Now multiply both sides of this equation by 6: 6b + b + 3b = 180
Now combine like terms: 10b = 180
Now divide both sides by 10: b = 180.
The dog's body is 18 inches long. Now divide that length by 2 to find the length of its tail: 18 inches / 2 = <<18/2=9>>9 inches
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