Guangming Village has 80 telephones this year, and 50 telephones last year. How many percent has it increased this year compared to last year?
光明村今年拥有电话80台，去年拥有电话50台，今年比去年增加了百分之几？
<gadget id="calculator">80 - 50</gadget>
<output>30</output>

<gadget id="calculator">30 / 50</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>