Brenda bakes 20 cakes a day. She does this for 9 days and then sells half of the cakes. How many cakes are left with Brenda?
After 9 days, Brenda bakes 20 * 9 = 
<gadget id="calculator">20*9</gadget>
<output>180</output>
180 cakes.
After she sells half of them, the remaining will be 180 / 2 = 
<gadget id="calculator">180/2</gadget>
<output>90</output>
90 cakes.

<result>90</result>