There are 325 students in the lower grades of Jianshe Primary School, and the number of students in the middle and upper grades is four times that of the lower grades. How many fewer students are there in the lower grades than in the middle and upper grades?
建设小学低年级有学生325人，中高年级学生人数是低年级的4倍．低年级学生比中高年级学生少多少人．
<gadget id="calculator">325 * 4</gadget>
<output>1_300</output>

<gadget id="calculator">1_300 - 325</gadget>
<output>975</output>

<result>975</result>