Answer: 17
Step-by-step explanation: Luckly, this question is multiple choice meaning that we could try all the solutions going backwords. We will start from 10. Since the length is 7 feet more than the width, we will do 10 - 7 to find the width. That gives you 3 and perimiter means we have to add up all the sides. 3 + 10 + 3 + 10 = 26 and 54 does not equal 54. Now we will do 17. 17 - 7 gives you 10. So, 17 + 10 + 17 + 10 = 54. 54 = 54 so your answer will be 17.