A village originally had 213 hectares of paddy fields and 92 hectares of dry land. Now it plans to transform part of the dry land into paddy fields so that the area of paddy fields is four times that of the dry land. How many hectares of dry land need to be transformed?
某村原有水田213公顷，旱地92公顷，现在计划把部分旱地改造为水田，使水田面积是旱地的4倍，需要改造旱地多少公顷？
<gadget id="calculator">213 + 92</gadget>
<output>305</output>

<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">305 / 5</gadget>
<output>61</output>

<gadget id="calculator">92 - 61</gadget>
<output>31</output>

<result>31</result>