In Mr. Smith's class, what is the ratio of the number of boys to the number of girls?
(1) There are 3 times as many girls as boys in Mr. Smith's class.
(2) The number of boys is 1/4 of the total number of boys and girls in Mr. Smith's class.
Official Guide question
Answer: D
In Mr. Smith's class, what is the ratio of
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Target question: What is the ratio of the number of boys to the number of girls?jjjinapinch wrote:In Mr. Smith's class, what is the ratio of the number of boys to the number of girls?
(1) There are 3 times as many girls as boys in Mr. Smith's class.
(2) The number of boys is 1/4 of the total number of boys and girls in Mr. Smith's class.
Official Guide question
Answer: D
Statement 1: There are 3 times as many girls as boys in Mr. Smith's class.
This means there are 3 girls for every 1 boy
So, the ratio of the number of boys to the number of girls = 3 : 1
Since we can answer the target question with certainty, statement 1 is SUFFICIENT
Statement 2: The number of boys is 1/4 of the total number of boys and girls in Mr. Smith's class.
So, for every 4 children there are 3 girls and 1 boy
So, the ratio of the number of boys to the number of girls = 3 : 1
Since we can answer the target question with certainty, statement 2 is SUFFICIENT
Answer: D
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Hi ALL,
We're asked for the ratio of the number of boys to the number of girls in Mr. Smith's Class. This question can be solved in a couple of different ways, including by TESTing VALUES.
1) There are 3 times as many girls as boys in Mr. Smith's class.
Based on the information in Fact 1, there could be....
1 boy and 3 girls, so the ratio is 1:3
2 boys and 6 girls, so the ratio is 2:6 = 1:3
3 boys and 9 girls, so the ratio is 3:9 = 1:3
Etc.
The ratio will ALWAYS be 1:3
Fact 1 is SUFFICIENT
2) The number of boys is 1/4 of the total number of boys and girls in Mr. Smith's class.
Based on the information in Fact 2, there could be....
1 boy and 4 total children (so there are 3 girls), so the ratio is 1:3
2 boys and 8 total children (so there are 6 girls), so the ratio is 2:6 = 1:3
3 boys and 12 total children (so there are 9 girls), so the ratio is 3: 9 = 1:3
Etc.
The ratio will ALWAYS be 1:3
Fact 2 is SUFFICIENT
Final Answer: D
GMAT assassins aren't born, they're made,
Rich
We're asked for the ratio of the number of boys to the number of girls in Mr. Smith's Class. This question can be solved in a couple of different ways, including by TESTing VALUES.
1) There are 3 times as many girls as boys in Mr. Smith's class.
Based on the information in Fact 1, there could be....
1 boy and 3 girls, so the ratio is 1:3
2 boys and 6 girls, so the ratio is 2:6 = 1:3
3 boys and 9 girls, so the ratio is 3:9 = 1:3
Etc.
The ratio will ALWAYS be 1:3
Fact 1 is SUFFICIENT
2) The number of boys is 1/4 of the total number of boys and girls in Mr. Smith's class.
Based on the information in Fact 2, there could be....
1 boy and 4 total children (so there are 3 girls), so the ratio is 1:3
2 boys and 8 total children (so there are 6 girls), so the ratio is 2:6 = 1:3
3 boys and 12 total children (so there are 9 girls), so the ratio is 3: 9 = 1:3
Etc.
The ratio will ALWAYS be 1:3
Fact 2 is SUFFICIENT
Final Answer: D
GMAT assassins aren't born, they're made,
Rich
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We need to determine the ratio of the number of boys to the number of girls. If we denote the number of boys as b and the number of girls as g, we can say:jjjinapinch wrote:In Mr. Smith's class, what is the ratio of the number of boys to the number of girls?
(1) There are 3 times as many girls as boys in Mr. Smith's class.
(2) The number of boys is 1/4 of the total number of boys and girls in Mr. Smith's class.
b/g = ?
Statement One Alone:
There are 3 times as many girls as boys in Mr. Smith's class.
We can create the equations:
g = 3b
g/b = 3
b/g = 1/3
Statement one is sufficient to answer the question.
Statement Two Alone:
The number of boys is 1/4 of the total number of boys and girls in Mr. Smith's class.
We can create the equation:
b = ¼(b + g)
4b = b + g
3b = g
b/g = 1/3
Statement two is sufficient to answer the question.
Answer: D
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