A cotton field collected 30 tons of lint last year, an increase of 5 tons over the previous year. How many percentages has the lint production of this cotton field increased?
一块棉花地，去年收皮棉30吨，比前年增产了5吨．这块棉花地皮棉产量增长了几百分之几？
<gadget id="calculator">30 - 5</gadget>
<output>25</output>

<gadget id="calculator">5 / 25</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>