Xiaohong bought a total of 13 stamps with a face value of 6 cents and 8 cents, and spent 8 yuan and 4 cents. How many stamps are there for 6 cents?
小红买票面是6角和8角的邮票一共13张，用去8元4角．6角的邮票有多少张．
<gadget id="calculator">84 / 10</gadget>
<output>42/5 = around 8.4</output>

<gadget id="calculator">10.4 - (42/5)</gadget>
<output>2</output>

<gadget id="calculator">8 / 10</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">6 / 10</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(4/5) - (3/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">2 / (1/5)</gadget>
<output>10</output>

<result>10</result>