There are 4 colors of red, yellow, green, and blue flowers, and every 2 colors are tied into a bunch. How many different ways are there?
有红，黄，绿，蓝4种颜色的花，每2种颜色扎成一束，有多少种不同的扎法．
<gadget id="calculator">4 - 1</gadget>
<output>3</output>

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

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

<result>6</result>