Uncle Wang has contracted a vegetable field. This year, he harvested 48.3 tons of cabbage, which is 15% more than last year. How many tons of cabbage did Uncle Wang harvest last year?
王叔叔承包了一块菜田，今年收白菜48.3t，比去年增产了一成五，王叔叔去年收白菜多少吨？
<gadget id="calculator">15 / 100</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">1 + (3/20)</gadget>
<output>23/20 = around 1.15</output>

<gadget id="calculator">48.3 / (23/20)</gadget>
<output>42</output>

<result>42</result>