Donna made a cake to take to a party where the guests ate half the cake. The day after the party, she shared half the leftovers with her brothers. The following day, she ate one piece as a midnight snack. Twice as many pieces as her snack were left. How many pieces was the cake to begin with?
Donna had 2 * 1 = 
<gadget id="calculator">2*1</gadget>
<output>2</output>
2 pieces of cake left.
Before her snack, there were 2 + 1 = 
<gadget id="calculator">2+1</gadget>
<output>3</output>
3 pieces left.
Those 3 pieces were half the leftovers, so she had 3 * 2 = 
<gadget id="calculator">3*2</gadget>
<output>6</output>
6 pieces before sharing with her brothers.
Those 6 pieces were half the party leftovers, so the cake was 2 * 6 = 
<gadget id="calculator">6*2</gadget>
<output>12</output>
12 pieces before the party.

<result>12</result>