The school carried out tree planting activities, 25 rows of pine saplings, 30 trees in each row. There are 30 rows of cypress seedlings, each with 18 trees. How many saplings of that kind? How many trees?
学校进行植树活动，松树苗25行，每行30棵．柏树苗有30行，每行18棵．那种树苗多？多多少棵？
<gadget id="calculator">25 * 30</gadget>
<output>750</output>

<gadget id="calculator">30 * 18</gadget>
<output>540</output>

<gadget id="calculator">750 - 540</gadget>
<output>210</output>

<result>210</result>