Stack 6 books of the same thickness, their height is 14 cm, and then stack 15 books of the same thickness on top, what is the total height of the stack of books?
将6本相同厚度的书叠起来，它们的高度为14厘米，再将15本这样相同厚度的书叠在上面，那么这叠书的总高度是多少？
<gadget id="calculator">14 / 6</gadget>
<output>7/3 = around 2.333333</output>

<gadget id="calculator">(7/3) * 6</gadget>
<output>14</output>

<gadget id="calculator">(7/3) * 15</gadget>
<output>35</output>

<gadget id="calculator">14 + 35</gadget>
<output>49</output>

<result>49</result>