The car dealer has 90 wheels in total, 15 bicycles are installed first, and the rest of the wheels are loaded with tricycles. How many tricycles can be loaded?
车行共进了90个车轮，先装了15辆自行车，其余的车轮装三轮车，可装多少辆三轮车？
<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<gadget id="calculator">90 - 30</gadget>
<output>60</output>

<gadget id="calculator">60 / 3</gadget>
<output>20</output>

<result>20</result>