Let x be the number of pairs of shoes that Becky owns.
Since 13 pairs is 5 less than twice as many pairs as Becky owns, then the relationship is 2x-5=13.
Adding 5 to each side of the equation, we get 2x=18.
Solving for x, we get x=<<9=9>>9.
Since Bobby has 3 times as many pairs of shoes as Becky has, then Becky has 3*9=<<3*9=27>>27 pairs of shoes.
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