The ratio of red to yellow is 4:5, red is 20 less than yellow, how many are red and yellow?
红与黄的比为4：5，红比黄少20个，红与黄共多少个？
<gadget id="calculator">20 * 4</gadget>
<output>80</output>

<gadget id="calculator">20 * 5</gadget>
<output>100</output>

<gadget id="calculator">80 + 100</gadget>
<output>180</output>

<result>180</result>