Question

Linear Equations
Exercise 2.2

Question 10: The number of boys and girls in a class are in the ratio 7:5. The number of boys is 8 more than the number of girls. What is the total class strength?

Answer 1

HELLO
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NUMBER OF BOYS AND GIRLS ARE IN RATIO 7:5 OR 7X AND 5X
7X-5X=8
2X=8
X=4
THE NO.S ARE 28 AND 20

Answer 2

boys =7x
girls=5x
total sthrenght=7x=5x=12x
therfor 7x=5x+8
7x-5x=8
2x=8,x=8/2=4
x=1four

so boys =7*4=28
girls=5*4=20
total =12*4=48students 
here the boys are 8 more than girls so first rule satisfied 
and the ratio =28/20=7/5=7:5 so second rule also satisfied so this answer is correct
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