Question

students of a school were made to stand in rows for drill. if 3 students less were standing in each row ,10 more rows were required and if five students more were standing in each row,then the number of rows was reduced by 10. find the number of students participating in the drill.
pls explain me anyone..

Answer 1

Let the number of rows be x and number of students in each row be y
Then total students will be=x*y
Now according to question
(x+10)(y-3)=xy
xy-3x+10y-30=xy
10y-3x=30-----------------(eq1)

Now..
(x-10)(y+5)=xy
xy+5x-10y-50=xy
5x-10y=50 ---------------(eq 2)
Adding eq 1 and 2 we get
2x=80
x=40
Putting x=40 in eq 1 we get
10y-120=30
10y=150
y=15

Answer 2

Answer:

Let row be the x and students be y

Step-by-step explanation:1st equ

(X+10)(y-3)=xy

10y-3x=30_ _ _1

5x-10y=50_ _ _2

Adding 1 &2

X=40

Y=15