There are 9 boxes of biscuits. If 14 packs of biscuits are taken from each box, then the number of packs remaining in the 9 boxes of biscuits is exactly equal to the number of packs left in the original 7 boxes of biscuits. How many packets of biscuits are there in each box?
有9盒饼干．如果从每盒中取出14包饼干，那么9盒饼干剩下的包数正好和原来7盒饼干的包数相等．原来每盒有多少包饼干．
<gadget id="calculator">9 - 7</gadget>
<output>2</output>

<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">14 * (9/2)</gadget>
<output>63</output>

<result>63</result>