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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A class contains boys and girls. What is the probability of selecting a boy from a class?
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BTGmoderatorDC
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Target question: What is the probability of selecting a boy from a class?BTGmoderatorDC wrote: ↑Thu Apr 13, 2023 12:04 amA 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
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
Answer: B
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