The grain store originally had (13/20) tons of rice. After selling (1/2) tons, it shipped in (7/10) tons. How many tons of rice does the grain store have now?
粮店原来有(13/20)吨大米，卖出(1/2)吨后，又运进(7/10)吨．粮店现在有大米多少吨？
<gadget id="calculator">13 / 20</gadget>
<output>13/20 = around 0.65</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(13/20) - (1/2)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(3/20) + (7/10)</gadget>
<output>17/20 = around 0.85</output>

<result>17/20 = around 0.85</result>