The number of calves that will be born as twins is 5 * 2 = <<5*2=10>>10 calves.
The total number of adults and calves before the trade is 9 + 5 + 9 + 10 = <<9+5+9+10=33>>33.
Jill had 33 - 8 = <<33-8=25>>25 left for trading 8 of the claves.
But, she got 2 adult llamas in return, so she now has a total of 25 + 2 = <<25+2=27>>27 llamas.
She then sold 27 / 3 = <<27/3=9>>9 llamas in the market.
So, Jill has 27 - 9 = <<27-9=18>>18 llamas now.
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