The number of pants Isabella bought is 21 / 3 = <<21/3=7>>7 pairs of pants.

The number of dresses Isabella bought is 18 / 3 = <<18/3=6>>6 dresses.

The total number of pants and dresses Isabella bought is 7 + 6 = <<7+6=13>>13.

# Answer

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<|im_start|>system
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<|im_start|>user
Isabella and Alexis went to the mall to buy some pants and dresses. Alexis bought 3 times more pants and dresses than Isabella. If Alexis bought 21 pairs of pants and 18 dresses, how many pairs of pants and dresses did Isabella buy in total?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
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user
13
Isabella and Alexis went to the mall to buy some pants and dresses. Alexis bought 3 times more pants and dresses than Isabella. If Alexis bought 21 pairs of pants and 18 dresses, how many pairs of pants and dresses did Isabella buy in total?
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