A pile of coal weighs (5/8) tons in total, (1/7) is burned on the first day, and (1/7) tons is burned on the second day. How many tons were burned in two days?
一堆煤共重(5/8)吨，第一天烧了(1/7)，第二天烧了(1/7)吨．两天共烧多少吨．
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">(5/8) * (1/7)</gadget>
<output>5/56 = around 0.089286</output>

<gadget id="calculator">(5/56) + (1/7)</gadget>
<output>13/56 = around 0.232143</output>

<result>13/56 = around 0.232143</result>