Grandma Wang bought three boxes of 20 cream popsicles at the wholesale department and spent 51.6 yuan. Then sell it at a price of 1.5 yuan each. After a box of popsicles is sold out, how much money do you make?
王奶奶在批发部买了三箱20支的奶油冰棍，花了51.6元．然后以每支1.5元的价格出售，一箱冰棍卖完后，赚了多少钱？
<gadget id="calculator">1.5 * 20</gadget>
<output>30</output>

<gadget id="calculator">51.6 / 3</gadget>
<output>17.2</output>

<gadget id="calculator">30 - 17.2</gadget>
<output>12.8</output>

<result>12.8</result>