Q2- question on percent

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Q2- question on percent

by [email protected] » Mon Oct 17, 2016 7:17 am
"If there are 80% as many as boys as girls" - what does that mean? Does that mean 80% of boys and 80% of girls? Please look at the question below

75% of all boys and 48% of all girls of Smith High School takes civics. If there are 80% as many boys as girls, what percent of all students take civics?

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by Brent@GMATPrepNow » Mon Oct 17, 2016 7:29 am
[email protected] wrote:"If there are 80% as many as boys as girls" - what does that mean? Does that mean 80% of boys and 80% of girls? Please look at the question below

75% of all boys and 48% of all girls of Smith High School takes civics. If there are 80% as many boys as girls, what percent of all students take civics?
There are 80% as many as boys as girls
This means that: # of boys = 80% of the number of girls
That is: # of boys = (0.80)(# of girls)


75% of all boys and 48% of all girls of Smith High School takes civics. If there are 80% as many boys as girls, what percent of all students take civics?
Let G = number of girls
So 0.8G = number of boys

75% of all boys take civics
Number of boys taking civics = 0.75(0.8G) = 0.6G

48% of all girls take civics
Number of girls taking civics = 0.48G

Total number of children taking civics = 0.6G + 0.48G = 1.08G
Total number of children in the school = G + 0.8G = 1.8G

PERCENTAGE of children taking civics = (100)(1.08G)/(1.8G)
= (100)(1.08)/(1.8)
= 605

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by [email protected] » Mon Oct 17, 2016 7:44 am
Dear Brent,

if I can pick a smart number and based on the logic you stated, i.e.

That is: # of boys = (0.80)(# of girls)

can I say that if there are 100 girls, we have 80 boys? Can you please explain with a smart number?