Claire was in charge of passing out free balloons to all the children at the fair.  She started with 50 balloons.  While passing 1 balloon to a little girl, 12 balloons floated away.  Over the next thirty minutes, she gave 9 more away and grabbed the last 11 from her coworker.  How many balloons does Claire have?
As she gave 1 balloon out, 12 balloons floated away plus she gave away 9 more balloons so she is down 1+12+9 = 
<gadget id="calculator">1+12+9</gadget>
<output>22</output>
22 balloons.
She started with 50 and gave/lost 22 balloons so she has 50-22 = 
<gadget id="calculator">50-22</gadget>
<output>28</output>
28 balloons.
She also took her coworkers last 11 balloons so her new total is 28+11 = 
<gadget id="calculator">28+11</gadget>
<output>39</output>
39 balloons.

<result>39</result>