When transporting a batch of fruits, 20% of the fruit is transported for the first time. If another 3 tons are transported, then the number of tons shipped at this time is three times the number of remaining tons. How many tons is this batch of fruit?
运一批水果，第一次运了20%，如果再运3吨，那么这时已运的吨数是剩下的吨数的3倍．这批水果有多少吨？
<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(3/4) - (1/4)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">3 / (1/2)</gadget>
<output>6</output>

<result>6</result>