A total of 5,400 teachers and students from schools A and B watched the "June 1" performance. It is known that school A watched the performance from school B (4/5). Find the number of people who watched the performance from school A (use the equation to solve it)
甲、乙两所学校观看"六一"汇演的师生共计5400人，已知甲校观看是乙校的(4/5)，求甲校观看汇演的人数(用方程解)
<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">5_400 / 9</gadget>
<output>600</output>

<gadget id="calculator">4 * 600</gadget>
<output>2_400</output>

<result>2_400</result>