There are 50 people in the first workshop, and the number of people in the second workshop is twice that of the first workshop. The sum of the number of people in the two workshops is 20 more than that in the third workshop. How many people are there in the third workshop? (Column comprehensive formula solution)
第一车间有50人，第二车间的人数是第一车间的2倍，这两车间的人数的和比第三车间的多20人，第三车间有多少人？(列综合算式解答)
<gadget id="calculator">50 * 2</gadget>
<output>100</output>

<gadget id="calculator">50 - 20</gadget>
<output>30</output>

<gadget id="calculator">100 + 30</gadget>
<output>130</output>

<result>130</result>