The green area of Dongzhuang Village reached 15 hectares this spring, but only 3/4 of the planned green area. How many hectares is the planned green area? (solution by equation)
东庄村今年春季绿化面积达到15公顷，但只是计划绿化面积的(3/4)，计划绿化面积达到多少公顷？(用方程解)
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">15 / (3/4)</gadget>
<output>20</output>

<result>20</result>