A monkey ate peaches from the tree, the first time it ate (1/30), and in the following 28 days, it stole (1/29), (1/28), ..., ( 1/3), (1/2). After 29 days of stealing, there are only 3 peaches left on the tree. How many peaches were there on the tree?
一只猴子偷吃树上的桃子，第一次偷吃了(1/30)，以后的28天，分别偷了当天现有桃子的(1/29)，(1/28)，…，(1/3)，(1/2)．偷了29天后，树上只剩下3个桃子．树上原有桃子多少个．
<gadget id="calculator">3 * 30</gadget>
<output>90</output>

<result>90</result>