Ivan had $10 and spent 1/5 of it on cupcakes. He then spent some money on a milkshake and had only $3 left. How much is the milkshake?
Ivan spent a total of $10 - $3 = $
<gadget id="calculator">10-3</gadget>
<output>7</output>
7 on cupcakes and a milkshake.
The cost of the cupcake is $10 x 1/5 = $
<gadget id="calculator">10*1/5</gadget>
<output>2</output>
2.
So, $7 - $2 = $
<gadget id="calculator">7-2</gadget>
<output>5</output>
5 was spent on the milkshake.

<result>5</result>