At Tyler High School, there are twice as many girls than boys on the

Expanding a bit on pushpitkc 's excellent answer in order to clear up possible language doubts.*

(1) Assign a number of girls in the club
# of girls in the club = 120
# of boys in the club hence = 60

(2) Assign the percentage of female club members who attend the meeting

OF the girls in the club, what percentage of those girls went to the meeting?
This choice is arbitrary. Make it easy to use.

Percentage of girls who attend meeting: 50%
Percentage of boys who attend meeting: 25%

3) calculate #s of persons at the meeting
Girls: 50% = \((.5*120)= 60\) girls
Boys: 25% = \((.25*60)=15\) boys
Total #: \((60+15)=75\) persons at the meeting

4) Boys = what percent of people at the meeting?
Percent: \(\frac{Part}{Whole}*100\)
Boys = 15
Total = 75

Percent of meeting attendees who were boys:
\((\frac{15}{75}*100)=(.20*100)=20\) percent

Answer A

This phrase: "the percentage of girls attending was twice the percentage of boys" does NOT mean that at the meeting, girls= 66.7% of attendees and boys = 33.3% of attendees.

There are TWO parts..

(I) Strength

there are twice as many girls than as boys on the yearbook staff --- so G=2B

(II) Meeting

the percentage of girls attending was twice the percentage of boys. What percent of those attending were boys
Now let the % of boys attending be x or 10%, then the % of girls attending be 2x or 20%.
Number of girls attending = 2x*G=2x*2B=4x*B
Number of girls attending =x*B

ANSWER

What percent of those attending were boys?
Total attending = 4x*B+x*B=5x*B
Boys = x*B

percent = \(\frac{x*B}{5x*B}*100=\frac{1}{5}*100=20%\)

Let number of girls = G and number of boys = B at THS.
Here G = 2B
Let number of girls present in meeting = g and number of boys = b
Now, \(\frac{g}{G} = 2\frac{b}{B}\)

Taking numbers as G = 100 and B = 50 and assuming \(\frac{g}{G} * 100 = 40%\), so \(\frac{b}{B} * 100 = 20%\)
Hence g = 40 and b = 10
Thus, \(\frac{b}{b + g} * 100 = 20%\)

Answer A.