Answer:
21/2
Step-by-step explanation:
The answer can be determined by substracting the lengrh of the woodland trail from the Marsh trail
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converting the fraction to its simplest form gives 21/2
3/18 divided 7/21 =3/18 multiply by 21/7 (we have to flip the second fraction and multiply by 3/18)= 63/126=1/2
So the answer is 1/2