When planting trees in schools, there are three planting methods: 12, 16 or 20 trees in each row, all of which are just arranged in a whole row without any surplus. Ask at least how many trees?
学校植树，每行栽12棵、16棵或20棵三种栽法，都刚好排成整行而无剩余．问至少有多少棵树？
<gadget id="calculator">2 * 2 * 3 * 2 * 2 * 5</gadget>
<output>240</output>

<result>240</result>