There are two grain depots, A and B, and A’s grain depot is twice that of B’s grain depot. If 30 tons are shipped from A’s grain depot every day, 50 tons are transferred to B’s grain depot. After 4 days, the grain stored in B’s grain depot will be the total 60%, how many tons of grain were originally stored in the two grain depots.
甲乙两粮库，甲粮库存库粮是乙粮库的2倍，如果每天从甲粮库运出30吨，给乙粮库调入50吨，这样4天后，乙粮库的存粮是总数的60%，两粮库原来存粮多少吨．
<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">30 * 4 * (3/5)</gadget>
<output>72</output>

<gadget id="calculator">50 * 4</gadget>
<output>200</output>

<gadget id="calculator">50 * 4 * (3/5)</gadget>
<output>120</output>

<gadget id="calculator">200 - 120</gadget>
<output>80</output>

<gadget id="calculator">72 + 80</gadget>
<output>152</output>

<gadget id="calculator">2 * (3/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(3/5) - 1</gadget>
<output>-2/5 = around -0.4</output>

<gadget id="calculator">(6/5) + (-2/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">152 / (4/5)</gadget>
<output>190</output>

<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">190 * 3</gadget>
<output>570</output>

<result>570</result>