There are 120 pieces of candy, if each person is divided into 3 pieces. Just finished dividing, if each person divides 4 pieces, how many pieces of candy should be prepared?
有120块糖，如果每人分3块．刚好分完，如果每人分4块，还要准备多少块糖？
<gadget id="calculator">120 / 3</gadget>
<output>40</output>

<gadget id="calculator">40 * 4</gadget>
<output>160</output>

<gadget id="calculator">160 - 120</gadget>
<output>40</output>

<result>40</result>