A barrel of oil weighs (2/25) tons, (1/20) of the barrel of oil is used for the first time, and (1/20) tons is used for the second time, how many tons are shared between the two times?
一桶油重(2/25)吨，第一次用去这桶油的(1/20)，第二次用去(1/20)吨，两次共用去多少吨？
<gadget id="calculator">2 / 25</gadget>
<output>2/25 = around 0.08</output>

<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(2/25) * (1/20)</gadget>
<output>1/250 = around 0.004</output>

<gadget id="calculator">(1/250) + (1/20)</gadget>
<output>27/500 = around 0.054</output>

<result>27/500 = around 0.054</result>