<human>:  Tanya went to the grocery store to buy some fruit. She bought 6 pears, 4 Granny Smith apples, 2 pineapples, and a small basket of plums, which were all placed in a single paper bag. Unfortunately, the bag that the fruit had been placed in had developed a hole. Therefore, as Tanya walked home, half of the fruit fell out of the bag. When she later counted the fruit left in the bag, there were only 9 pieces remaining. How many plums did she buy?
<bot>: How many pieces of fruit did Tanya buy? ** If half of the fruit equals 9 pieces, then Tanya bought 2*9=<<2*9=18>>18 pieces of fruit.
How many plums did Tanya buy? ** Thus, Tanya bought 18-6-4-2=<<18-6-4-2=6>>6 plums.
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