A mum ordered 80 cupcakes for her daughter's birthday. Half of them are gluten-free. There are 24 vegan cupcakes and half of them are also gluten-free.  How many are non-vegan cupcakes that also contain gluten?
The gluten-free cupcakes are 80 / 2 = 
<gadget id="calculator">80/2</gadget>
<output>40</output>
40.
The vegan cupcakes with gluten are 24 / 2 = 
<gadget id="calculator">24/2</gadget>
<output>12</output>
12.
The non-vegan cupcakes with gluten are 40 - 12 = 
<gadget id="calculator">40-12</gadget>
<output>28</output>
28.

<result>28</result>