Emily bought 9 packs of candy necklaces to give her classmates at school for Valentine’s Day. Each pack had 8 candy necklaces in it. Emily opened one pack at a time. After her classmates took as many as they wanted, there were 40 candy necklaces left. How many packs did Emily open for her classmates?
Emily bought 9 packs of candy necklaces * 8 candy necklaces in a pack = 
<gadget id="calculator">9*8</gadget>
<output>72</output>
72 candy necklaces.
Her classmates took 72 candy necklaces - 40 candy necklaces left = 
<gadget id="calculator">72-40</gadget>
<output>32</output>
32 candy necklaces.
Since each pack contained 8 necklaces, this means 32 / 8 = 
<gadget id="calculator">32/8</gadget>
<output>4</output>
4 packs of candy necklaces were opened.

<result>4</result>