The weight ratio of the two bags of sugar between A and B is 3:1. If 100 grams are taken out from bag A and put into bag B, the weight ratio of the two bags of sugar becomes 7:5, then the sum of the weight of the two bags of sugar How many grams?
甲、乙两包糖的重量之比是3：1，如果从甲包取出100克放入乙包后，甲乙两包糖的重量之比变为7：5，那么这两包糖重量的总和是多少克？
<gadget id="calculator">3 + 1</gadget>
<output>4</output>

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

<gadget id="calculator">7 + 5</gadget>
<output>12</output>

<gadget id="calculator">7 / 12</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">(3/4) - (7/12)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">100 / (1/6)</gadget>
<output>600</output>

<result>600</result>