A copy of "Composition World" is 3 cm thick, and an exercise book is 5 mm thick. How many times thicker is this "Composition World" than this exercise book?
一本《作文天地》厚3厘米，一本练习本厚5毫米，这本《作文天地》的厚度是这本练习本厚度的几倍？
<gadget id="calculator">30 / 5</gadget>
<output>6</output>

<result>6</result>