Question

in a class of 49 students number of girls is 2 by 5 of the boys find the number of boys in the class

Answer 1

Solution

Le no of rows = x and no of student in each row y
total no of student x*y
By given condition 
(x-2)(y+4)=xy (i)
(x+4)(y-4)=xy (ii)
Solve 
x=8, y=12
no of student = 12*8 = 96


YOU CAN SOLVE THIS PROBLEM LIKE THIS

Answer 2

let the no. of boys in the school be X
let the no. of girls in the school be 2X/5

ATQ,

2/5X+X=49
(2X+5X)/5=49
7X/5=49
7X=245
X=245/7
X=35

NO. of boys =35
No. of girls = 49-35= 14


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