Granary A has 120 tons of flour, and Granary B has 96 tons of flour. Granary A transports 20 tons of flour every day, and Granary B transports 8 tons of flour every day. After how many days, the tonnage of flour in Granary A will be 2 tons of flour in Granary B. Times.
甲粮仓有120吨面粉，乙粮仓有96吨面粉，甲粮仓每天运进20吨面粉，乙粮仓每天运进8吨面粉，多少天以后，甲粮仓的面粉吨数是乙粮仓面粉吨数的2倍．
<gadget id="calculator">192 - 120</gadget>
<output>72</output>

<gadget id="calculator">72 / 4</gadget>
<output>18</output>

<result>18</result>