A 20-acre experimental field (3/5) is planted with peaches, and the field planted with peaches accounts for (4/3) of the field planted with watermelons. How many mu is the field planted with watermelons?
一块20亩的试验田(3/5)种桃子，而种桃子的田又占了种西瓜的田的(4/3)，问种西瓜的田是多少亩？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">4 / 3</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">(3/5) / (4/3)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">20 * (9/20)</gadget>
<output>9</output>

<result>9</result>