There are 168 pear trees in the orchard, and twice as many peach trees as pear trees. How many fruit trees are there in the orchard?
果园有梨树168棵，桃树的棵数是梨树的2倍．果园里一共有多少棵果树？
<gadget id="calculator">168 * 2</gadget>
<output>336</output>

<gadget id="calculator">336 + 168</gadget>
<output>504</output>

<result>504</result>