The school cafeteria ordered 8 red apples and 43 green apples for students lunches. But, if only 42 students wanted fruit, how many extra did the cafeteria end up with?
<gadget id="calculator">8 + 43</gadget>
<output>51</output>

<gadget id="calculator">51 - 42</gadget>
<output>9</output>

<result>9</result>