Question 384393: 1. In a certain class, the average weight of girls is 10 kg less than the average weight of all the students, and the average weight of boys is 5 kg more than the average weight of all the students. What percent of the students in the class are girls?
(A) 20% (B) 25% (C) 33.33% (D) 35% (E) 40%
2. At a soccer match, the contractor provided dinner for 24 players, and fixed the price per person so as to gain 12.5% on his total outlay. However, 3 of the players were absent and the remaining 21 players paid the fixed price for their dinner and as such the contractor lost $1 on his total outlay. What was the charge of the dinner per person?
(A) $3 (B) $3.5 (C) $4.0 (D) $5 (E) $ 6
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 1. In a certain class, the average weight of girls is 10 kg less than the average weight of all the students, and the average weight of boys is 5 kg more than the average weight of all the students. What percent of the students in the class are girls?
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Let the average wt. of all students be "x".
Average wt. of the girls is (x-10)
Weight of all the girls is (x-10)g
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Weight of all the boys is (x+5)b
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# of students = b+g
Wt of all students is (x-10)g+(x+5)b
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Equation:
Average wt of all students = x
[(x-10)g + (x+5)b]/(b+g) = x
[gx-10g + bx+5b]/(b+g) = x
[(b+g)x + 5b-10g] = (b+g)x
5b-10g = 0
b = 2g
The 3 of boys is twice the number of girls.
Percent of girls = 33.33%
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(A) 20% (B) 25% (C) 33.33% (D) 35% (E) 40%
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Cheers,
Stan H.
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2. At a soccer match, the contractor provided dinner for 24 players, and fixed the price per person so as to gain 12.5% on his total outlay. However, 3 of the players were absent and the remaining 21 players paid the fixed price for their dinner and as such the contractor lost $1 on his total outlay. What was the charge of the dinner per person?
(A) $3 (B) $3.5 (C) $4.0 (D) $5 (E) $ 6
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