Question

ane-half the sum of the sides of the mangle
From a group of boys and girls, 15 girls leave. There are then left two boys for each girl
45 boys leave, there are then 5 girls for each boy, The number of girls in the begining was
1) 40
3) 29
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Answer 1

Answer:

no of girls is 40:- a) 40

Step-by-step explanation:

let no of girls at start be x

when 15 girls leave

no of girls is x-15

there are 2 boys for each girl

no of boys is 2(x-15) = 2x-30

when 45 boys leave

no of boys is 2x-30-45=2x-75

now, there are 5 girls for each boy

hence, no of girls is 5(2x-75) = 10x - 375

but this is equal to x-15 since no of girls has not changed.

=>x-15 =10x-375

9x=360

x=40

no of girls is 40

Answer 2

Answer:

Algebraically;

B=2(G-15)

5(B-45)=G-15

PIN:

G=29; G-15=14; B=14*2=28; How can 45 boys leave out of 28.

G=40; G-15=25; B=25*2=50; 50-45=5; 5*5=25. Matches the count of girls.

Ans: 1. 40