There is a barrel of oil, 30 kilograms are taken out on the first day, 1/4 less (1/4) is taken out on the second day than on the first day, and 30% of the whole barrel of oil is taken out on the second day, how many kilograms of this barrel of oil are there in total?
有一桶油，第一天取出30千克，第二天比第一天少取(1/4)，第二天取出整桶油的30%，这桶油共多少千克．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(3/4) / (3/10)</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">30 * (5/2)</gadget>
<output>75</output>

<result>75</result>