Sea turtles can live 180 years, 20 years more than twice the lifespan of an elephant. How many years can an elephant live? (equation solution)
海龟可以活180年，比大象的寿命的2倍还多20年，大象能活多少年？(方程解)
<gadget id="calculator">180 - 20</gadget>
<output>160</output>

<gadget id="calculator">160 / 2</gadget>
<output>80</output>

<result>80</result>