There are 50 motorcycles and cars in the parking lot. The total number of wheels is 160. How many cars are there in the parking lot?
在停车场上有摩托车和小汽车共50辆，车轮的总数是160个，停车场上有小汽车多少辆．
<gadget id="calculator">50 * 2</gadget>
<output>100</output>

<gadget id="calculator">160 - 100</gadget>
<output>60</output>

<gadget id="calculator">4 - 2</gadget>
<output>2</output>

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

<result>30</result>