There is a bag of rice, 40% of the bag of rice was eaten in the first week, and (3/10) of the bag of rice in the second week left 6 kilograms. How many kilograms did the bag of rice originally have?
有一袋大米，第一周吃去了这袋大米的40%，第二周这袋大米的(3/10)，还剩6千克，这袋大米原有多少千克？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (2/5) - (3/10)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">6 / (3/10)</gadget>
<output>20</output>

<result>20</result>