The students carried water to water the trees. The third grade watered 55 trees, the fourth grade watered 18 more trees than the third grade, and the fifth grade watered twice as many trees as the fourth grade. How many trees did the fifth grade water?
同学们抬水浇树，三年级浇了55棵，四年级比三年级多浇了18棵，五年级浇的棵树是四年级的2倍．五年级浇了多少棵？
<gadget id="calculator">55 + 18</gadget>
<output>73</output>

<gadget id="calculator">73 * 2</gadget>
<output>146</output>

<result>146</result>