Q10

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Q10

by magical cook » Wed Oct 31, 2007 8:39 am
If each of the students in a certain mathematics class is either a junior or a senior, how
many students are in the class?
(1) If one student is to be chosen at random from the class to attend a conference,
the probability that the student chosen will be a senior is 4/7.
(2) There are 5 more seniors in the class than juniors.


Can anyone help - OA will forllow.
Source: — Data Sufficiency |

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by ri2007 » Wed Oct 31, 2007 9:15 am
I would say ans is C

Statement 1) Ratio of S:J = 4:3

Statement 2) S = J + 5

Combined - 4x = 3x +5, so x = 5

So total studients in the class = 35

Pls confirm

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by magical cook » Wed Oct 31, 2007 9:40 am
Yesh that's correct - thanks!