this quest looks easy, but i want 2 reconfirm...
In a certain class, one student has to be selected at random to read. what i sthe probability that a boy will read?
1. 2/3rd of the students in the class are boys.
2. 10 of the students in the class are girls.
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g_beatthegmat
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(A) it is.
Statement one gives us the fraction of boys in the class room. That's our probability as well, out of every 3 students in the class, 2 are boys - 2/3 ~ 66.6%
Statement two does not tell us how many boys are in the class. No sufficient.
ps: mathematically the above probability might be correct, but practically, whether the boy selected to read would *read* or not can never be determined
Statement one gives us the fraction of boys in the class room. That's our probability as well, out of every 3 students in the class, 2 are boys - 2/3 ~ 66.6%
Statement two does not tell us how many boys are in the class. No sufficient.
ps: mathematically the above probability might be correct, but practically, whether the boy selected to read would *read* or not can never be determined
