Xishan Orchard originally had 36 rows of apple trees, and each row had the same number of trees. This year, we plan to plant 15 more rows. We need to purchase 675 apple saplings. How many apple trees are there in Xishan Orchard?
西山果园原有36行苹果树，每行的棵数相等，今年打算再栽这样的15行，需要购进苹果树苗675棵，西山果园原有苹果树多少棵？
<gadget id="calculator">675 / 15</gadget>
<output>45</output>

<gadget id="calculator">45 * 36</gadget>
<output>1_620</output>

<result>1_620</result>