A barrel of oil weighs 80 kilograms, and (1/4) is used for the first time, and the rest (2/5) is used for the second time, how many kilograms of oil is used for the second time?
一桶油重80千克，第一次用去(1/4)，第二次用去余下的(2/5)，第二次用油多少千克？
<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">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/4) * (2/5)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">80 * (3/10)</gadget>
<output>24</output>

<result>24</result>