Divide a piece of cake equally among 8 children. After each child eats 2 pieces of cake, there are 4 pieces left. How many pieces is this cake divided into?
把一块蛋糕平均分给8个小朋友，每个小朋友吃了2块蛋糕后，还剩下4块．这块蛋糕分成了多少块．
<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<gadget id="calculator">16 + 4</gadget>
<output>20</output>

<result>20</result>