Question

Heyã❣️

Question :-

In a class of 60 students , each boy contributed rupees equal to the number of girls and each girl contributed rupees equal to the number of boys if total money collected was 1600 . How many boys are there in class

Please answer

Answer 1

Step-by-step explanation:

Let us consider the members to be x and Y...

xy + xy = 1600

=2xy = 1600

=xy = 1600/2

= y = 800/x --- ( 2 )

From ( 1 ) & ( 2 )

x + ( 800/x ) = 60

=x² + 800 = 60x

=x² - 40x - 20x + 800 = 0

=x( x - 40 ) - 20( x - 40 ) = 0

=

x - 40 = 0 Or x - 20 = 0

=x = 40

x = 20

Answer 2

Answer:

Step-by-step explanation:

Total strength of class = 60

Let no.of.boys = x

No.of.girls = 60-x

Distribution of each boy = no.of.girls

=> 60-x

Total contribution of boys = x(60-x) = 60-$x^{2}$

Contribution of each girl = no.of.boys=x

Total contribution = (60-x)x = 60x- $x^{2}$

According to question,

Total contribution = ₹1600

Boys + girls = ₹1600

60x - x^2 + 60x -x^2 = 1600

120x - 2x^2 = 1600

2x^2 -120x +1600=0

x^2 -60x + 800 = 0

x^2 -40x-20x+800 = 0

x(x-40)-20(x-40) = 0

(x-20) or (x-40) = 0

x = 40 or x = 20

So there are 40/20 boys