The length of a rectangle is 18 decimeters. If the length is increased by (1/3), how much should the width be reduced to keep the area of the rectangle constant?
一个长方形的长是18分米，如果把长增加它的(1/3)，要使长方形面积不变，宽应当减少多少．
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>