For Halloween Robin scored 23 pieces of candy. She ate 7 pieces the first night and then her sister gave her 21 more pieces. How many pieces of candy does Robin have now?
<gadget id="calculator">23 + 21</gadget>
<output>44</output>

<gadget id="calculator">44 - 7</gadget>
<output>37</output>

<result>37</result>