An adult eats 2 pieces of bread for a meal, and two children share a piece of bread for a meal. Now the adults and children together share a person, and they just ate a piece of bread. What percentage of the number of children is the number of adults?
一个大人一餐吃2个面包，两个小孩一餐合吃一个面包，现在大人、小孩合在一起共a人，刚好吃了a个面包，求大人人数是小孩人数的几分之几？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>