A warehouse shipped out 4 batches of raw materials, the first batch accounted for half of the warehouse inventory, the second batch accounted for the remaining half, each subsequent batch shipped the remaining half, and after the fourth batch was shipped out, the remaining raw materials were all For factories A, B, and C, factory A gets (1/3), factory B gets (1/2), and factory C gets 7 tons. How many tons of raw materials are there in the warehouse at first?
某仓库运出4批原料，第一批占仓库库存的一半，第二批占余下的一半，以后每一批都运出剩下的一半，第四批运出后，剩下的原料全部分给甲、乙、丙三厂，甲厂得(1/3)，乙厂得(1/2)，丙厂得7吨，问最初仓库里有多少吨原料？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (1/3) - (1/2)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">7 / (1/6)</gadget>
<output>42</output>

<gadget id="calculator">42 * 2 * 2 * 2 * 2</gadget>
<output>672</output>

<result>672</result>