Louise is hanging 30 of her pictures on the wall. She hangs some of them vertically, half of them horizontally, then hangs the remaining 5 pictures haphazardly. How many pictures did Louise hang vertically?
There are 30 / 2 = 
<gadget id="calculator">30/2</gadget>
<output>15</output>
15 pictures hanging horizontally.
So there is a total of 15 + 5 = 
<gadget id="calculator">15+5</gadget>
<output>20</output>
20 pictures hanging either horizontally or haphazardly.
Therefore, there are 30 - 20 = 
<gadget id="calculator">30-20</gadget>
<output>10</output>
10 pictures hanging vertically.

<result>10</result>