Question 1021678
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T=tricycles; B=bicycles
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T+B=31
T=31-B
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3T+2B=77
3(31-B)+2B=77
93-3B+2B=77
-B=-16
B=16
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T=31-B=31-16=15
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ANSWER: There are 16 bicycles and 15 tricycles.
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CHECK:
3T+2B=77
3(15)+2(16)=77
45+32=77
77=77
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