Ten years ago, there were only 50 color TV sets in a certain village, but now there are 648 color TV sets in the whole village, which is an increase of what percentage compared to ten years ago?
十年前某村全村只有50台彩电，现在全村共有648台彩电，比十年前增加了百分之几？
<gadget id="calculator">648 - 50</gadget>
<output>598</output>

<gadget id="calculator">598 / 50</gadget>
<output>299/25 = around 11.96</output>

<result>299/25 = around 11.96</result>