A pencil was originally 15 cm long, but 8 mm has been used. How long is the pencil?
一支铅笔原来长15厘米，用去了8毫米，这支铅笔还有多长？
<gadget id="calculator">15 * 10</gadget>
<output>150</output>

<gadget id="calculator">150 - 8</gadget>
<output>142</output>

<result>142</result>