There are 42 students in the third grade, 24 people in a big boat and 6 people in a small boat. The students fill up the big boat first, and the rest take small boats. How many small boats are needed at least? What is the column
三年级共有42人，一条大船坐24人，一条小船坐6人，同学们先坐满一条大船，剩下的坐小船，至少需要几条小船？列式是多少
<gadget id="calculator">42 - 24</gadget>
<output>18</output>

<gadget id="calculator">18 / 6</gadget>
<output>3</output>

<result>3</result>