Xiaofan bought 4 pieces of erasers, x yuan each, and Xiaofan paid the salesperson 10 yuan, how much should be returned.
小帆买了4块橡皮，每块x元，小帆付给售货员10元，应找回多少元．
<gadget id="calculator">10 - 4</gadget>
<output>6</output>

<result>6</result>