Xiao Ming bought 3 pencils, Xiao Hong bought 7 pencils and paid 1 yuan and 2 jiao more than Xiao Ming, how much is each pencil.
小明买了3枝铅笔，小红买了7枝铅笔比小明多付1元2角，每枝铅笔多少角．
<gadget id="calculator">7 - 3</gadget>
<output>4</output>

<gadget id="calculator">1.2 / 4</gadget>
<output>0.3</output>

<gadget id="calculator">0.3 * 10</gadget>
<output>3</output>

<result>3</result>