There are four members in Xiaoming's family. If two people are selected for a group photo each time, how many different ways are there to choose?
小明一家有四口人，如果每次选2人合影，有多少种不同的选法．
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">4 * (3/2)</gadget>
<output>6</output>

<gadget id="calculator">2 * 1</gadget>
<output>2</output>

<gadget id="calculator">6 * 2</gadget>
<output>12</output>

<result>12</result>