Question 1108410
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<pre>
Had all 24 boxes be pen boxes, it would be totaled 10*24 = 240 dollars, exceeding 200 dollars by 40 dollars.


Hence, I must replace some of 24 pen boxes by more cheaper $5 boxes to zero the difference.


By replacing each box, I decrease the difference by $5.


So, the number of the $5 box must be {{{40/5}}} = 8.


Then the number of the $10 boxes is 24-8 = 16.
</pre>

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