## A class contains boys and girls. What is the probability of selecting a boy from a class?

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### A class contains boys and girls. What is the probability of selecting a boy from a class?

by BTGmoderatorDC » Thu Apr 13, 2023 12:04 am

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## Global Stats

A class contains boys and girls. What is the probability of selecting a boy from a class?

(1) There are 35 students in the class
(2) The ratio of boys to girls is 3:4

OA B

Source: Magoosh

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### Re: A class contains boys and girls. What is the probability of selecting a boy from a class?

by Brent@GMATPrepNow » Sat Apr 15, 2023 6:56 am

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B

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## Global Stats

BTGmoderatorDC wrote:
Thu Apr 13, 2023 12:04 am
A class contains boys and girls. What is the probability of selecting a boy from a class?

(1) There are 35 students in the class
(2) The ratio of boys to girls is 3:4

OA B

Source: Magoosh
Target question: What is the probability of selecting a boy from a class?

Statement 1: There are 35 students in the class
In order to determine the probability of selecting a boy, we need to know what fraction of the 35 students are boys.
So, as it stands, statement 1 is NOT SUFFICIENT

Statement 2: The ratio of boys to girls is 3:4
This means that, out of every 7 children, 3 of them are boys, and 4 of them are girls.
So, P(selecting a boy) = 3/7
Since we can answer the target question with certainty, statement 2 is SUFFICIENT