A bag of soybeans and a bag of mung beans weigh 50 kg in total, and 5 bags of soybeans and 3 bags of mung beans weigh a total of 210 kg. How much does a bag of soybeans weigh in kilograms?
一袋黄豆和一袋绿豆共重50千克，买5袋黄豆和3袋绿豆共重210千克．一袋黄豆重多少千克．
<gadget id="calculator">50 * 3</gadget>
<output>150</output>

<gadget id="calculator">210 - 150</gadget>
<output>60</output>

<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">60 / 2</gadget>
<output>30</output>

<result>30</result>