Multiply the number of yellow balloons by 3 and subtract 12 to get the same number of red balloons, which are 90. How many yellow balloons are there?
黄气球的个数乘3，再减去12个，就和红气球的个数同样多，红气球有90个．黄气球有多少个？
<gadget id="calculator">90 + 12</gadget>
<output>102</output>

<gadget id="calculator">102 / 3</gadget>
<output>34</output>

<result>34</result>