Respuesta :

Answer:

A school has 9 grades and 5 of the grades have 20 fewer students than the other 4. The school has 584 students. How many students are in the 5 with fewer students?

Total number of students in 5 of the grades = 280

Step-by-step explanation:

Let the number of students in each of (other 4) grades be 'x'

There are 4 grades so total no. of students in (other 4) = 4x

Now

Number of students in each (5 of the grades) = (x-20)

Total number of student in (5 of the grades) = 5(x-20)

According to the question:

⇒ [tex]4x+5(x-20)=584[/tex]

⇒ [tex]4x+5x-100=584[/tex]

⇒ [tex]9x-100=584[/tex]

Adding 100 both sides.

⇒ [tex]9x-100+100=584+100[/tex]

⇒ [tex]9x=684[/tex]

Dividing 9 both sides.

⇒ [tex]x=\frac{684}{9}[/tex]            

⇒ [tex]x=76[/tex] students.

Number of students in 5 of the grades were the students are fewer:

⇒ [tex]5(x-20)=5(76-20)=5(56)=280[/tex]

Total number of students in 5 of the grades = 280