Xiao Ming went to the bookstore and bought 20 math books. The height of the stack is 120 cm. The height of the other stack is 24 cm. Ask: How many books are there in this stack? (comprehensive answers)
小明去书店买了20本数学书，摞在一起有120厘米高，同样的另一摞书高24厘米，问：这摞书有几本？(列综合式解答)
<gadget id="calculator">120 / 20</gadget>
<output>6</output>

<gadget id="calculator">24 / 6</gadget>
<output>4</output>

<result>4</result>