each girl in the lynberg family has the same number of brothers as she gas sisters.each boy in the lynberg family has twise as many sisters as he has brothers. How many girls and boys are in the lynberg family?
2006-11-27 10:03:12 · 6 answers · asked by Anonymous in Education & Reference ➔ Homework Help
let x be girls, and y be boys
take a girl...she'll have (x -1) sisters (because excluding herself) and y brothers
so, x-1 = y........(1)
again, take a boy...he'll have (y-1) brothers and x sisters and its given 2(y-1) = x.......(2)....( sisters are twice the brothers)
now equate....
from (2).
2y - 2 = x.......(3)
put in (1)
2y - 2 -1 = y
or 2y - y = 3
or y = 3
therefore x = y+1 =4
so the girls are 4 , and boys are three
so any girl has three brothers and 3 sisters
any boy has 2 brothers and 4 sisters.
2006-11-27 10:12:17 · answer #1 · answered by amateur_astrologer 2 · 0⤊ 0⤋
S = number of sisters
B = number of brothers
L = B + (B +1) or 2B + 1.
(She has one more sister than brothers, since the number of brothers = sisters, so S = B+1)
L = 2(B-1) + S, since the boy's brothers (subtracting himself).
So 2B - 2 + S = 2B + 1, or S = 3. So there are 4 girls and 3 boys.
Checking - for a sister, she has 3 brothers and 3 sisters. For a brother, he has 4 sisters and 2 brothers. Thus we are correct.
2006-11-27 18:22:12 · answer #2 · answered by Anonymous · 0⤊ 0⤋
There are 3 kids total. Two girls and one boys. The girl has one one brother, which means she has one sister. Since shes a girl and has a sister, there are two girls in the family. And the boy has twice as many sisters, and the number of sisters is two, then there is one boy.
2006-11-27 18:12:08 · answer #3 · answered by Phillip P 2 · 0⤊ 1⤋
for the girl, she would not include herself as a sister, the boy does not include himself in brothers. Sorry but, that is about all I can tell you. I can't quite think.
2006-11-27 18:11:10 · answer #4 · answered by ruth4526 7 · 0⤊ 1⤋
clearly there is one more girl than there are boys. wasn't much help the next person that tries to answer has a place to start
2006-11-27 18:09:43 · answer #5 · answered by alpha mutt 4 · 0⤊ 0⤋
(EDIT) Gonna try again, but I am not the first to answer a correct question scroll down and give them best answer, I just want to try to do it myself to see
girls x boys y
x=y+1
2(y-1)= x
2y-2=y+1
y=3
ok 3 boys
plug that in
x=3+1
4
4 Girls
I finally figured it out, but no I didn't get it first it was after checking my answer and seeing it was wrong and editting, so give best answer to the next guy
2006-11-27 18:09:50 · answer #6 · answered by pululu81 4 · 0⤊ 1⤋