<human>:  Benny threw bologna at his balloons. He threw two pieces of bologna at each red balloon and three pieces of bologna at each yellow balloon. If Benny threw 58 pieces of bologna at a bundle of red and yellow balloons, and twenty of the balloons were red, then how many of the balloons in the bundle were yellow?
<bot>: How many pieces of bologna did Benny throw at red balloons in the bundle? ** If Benny had twenty red balloons in the bundle, and he threw two pieces of bologna at each red balloon, then he threw 2*20=40 pieces of bologna at red balloons in the bundle.
How many pieces of bologna did Benny throw at yellow balloons in the bundle? ** If he threw a total of 58 pieces of bologna at balloons in the bundle, then he threw 58-40=<<58-40=18>>18 pieces of bologna at yellow balloons.
How many yellow balloons were in the bundle? ** If he threw three pieces of bologna at each yellow balloon, then he had 18/3=<<18/3=6>>6 yellow balloons.
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