Teacher Wang took 71.2 yuan to the stationery store and bought a pen with 29.2 yuan. How much money is left?
王老师带了71.2元去文具店，用29.2元买了钢笔，剩下多少元钱？
<gadget id="calculator">71.2 - 29.2</gadget>
<output>42</output>

<result>42</result>