Red, yellow and green balls are placed in a bag, of which red balls account for 25%, the ratio of the number of yellow balls to the other two balls is 1:2, there are 50 green balls, and there are three balls in total. how many?
红、黄、绿三种小球放在一个袋子里，其中红球占25%、黄球与另外两种球的个数和的比是1：2，绿球有50个，三种球共有多少个？
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(2/3) - (1/4)</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">50 / (5/12)</gadget>
<output>120</output>

<result>120</result>