How many ways are there to choose 3 out of 5 children to participate in a handicraft competition?
在5个小朋友中选3个参加手工比赛，有多少种选法．
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<result>10</result>