解:设树上原有x个桃子,第一天摘(1/2x+1)个,还剩【x-(1/2x+1)】个,第二天摘{1/2【x-(1/2x+1)】+1}个,还剩16个。【x-(1/2x+1)】-{1/2【x-(1/2x+1)】+1}=16解得x=70答:树上原有70个桃