Warehouse A stores 540 tons of grain, and Warehouse B stores 200 tons of grain. If the grain stored in Warehouse A is three times that of Warehouse B, how many tons must be transported from Warehouse B to Warehouse A?
甲仓库存粮540吨，乙仓库存粮200吨，要使甲仓库的存粮是乙仓库的3倍，那么必须从乙仓库运出多少吨放入甲仓库？
<gadget id="calculator">540 + 200</gadget>
<output>740</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">740 / 4</gadget>
<output>185</output>

<gadget id="calculator">200 - 185</gadget>
<output>15</output>

<result>15</result>