After a piece of chalk is used up. There are 9 mm left, and the total length of this piece of chalk is 7 cm 2 mm. How many times is the length of the remaining chalk used?
一根粉笔用去一些后．还剩9毫米，这根粉笔共长7厘米2毫米，用去的粉笔是剩下的粉笔长度的多少倍？
<gadget id="calculator">72 - 9</gadget>
<output>63</output>

<gadget id="calculator">63 / 9</gadget>
<output>7</output>

<result>7</result>