Question

A garden path is constructed with rectangular stone pavers of equal length and a gravel strip between each pair of consecutive pavers. Each gravel strip is as long as a paver. The total length of the path from the start of the first paver to the end of the last paver is 420 inches. If is an integer and the length, in inches, of each gravel strip is an integer greater than 10, what is the value of ?
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Answer Choices

  • A.
  • B.
  • C.
  • D.
  • E.

Steps

ExplanationCalculationsHelp
We pick as the length of each paver and as the length of each gravel strip.
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TRANS1-A
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We translate "The total length of the path from the start of the first paver to the end of the last paver is 420 inches." into an equation.
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TRANS1-B
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TRANS1-C
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We translate into an equation.
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TRANS1-E
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We substitute into the total-length equation and simplify.
We need to be an integer greater than 10, and since , we let so that .
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TRANS1-A
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We replace in and simplify.
We look for integer solutions to with so that , and we find that .
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Final Answer

C