Given:
The principal approved the event for 200 students.
The number of juniors should be 25% of the number of seniors.
To find:
The number of juniors.
Step-by-step explanation:
Let x be the number of seniors.
According to the problem,
![x+25\%\text{ of }x=200](https://img.qammunity.org/2023/formulas/mathematics/college/eb1uago7su6e20x5e7cktdpr2aawze2129.png)
Solve for x we get,
![\begin{gathered} x+(25)/(100)x=200 \\ x+(1)/(4)x=200 \\ (5x)/(4)=200 \\ 5x=800 \\ x=(800)/(5) \\ x=160 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/d9c4y1bsv8h7nb89bmcaccrvucrjp9i7ml.png)
So, the number of seniors is 160.
Therefore, the number of juniors must be,
![200-160=40](https://img.qammunity.org/2023/formulas/mathematics/college/5zuqzzdb5wqtmfv2fth9clqwgermo3t9k8.png)
Final answer:
The number of juniors is 40.