1. Good post? |

## Probability DS

What is the probability that a student randomly selected from a class of 60 students will
be a male who has brown hair?
(1) One-half of the students have brown hair.
(2) One-third of the students are males.

I thought it was C

SPOILER:

2. Good post? |
Let's call B the brown hair and M the males. Not-B are Blonde, Red,... F are females. Now draw the table:

______|__M___|___F__|___Total__
B_____|__X___|_______|____30___
Not-B |_______|_______|____30___
Total _|__20___|___40__|____60___

In red, the data provided or deduced from Proposition 1
In blue the one provided by proposition 2

We're looking for X (student simultanously Males AND with Brown hair), since the probability we're looking for is X/60.
Obviously, we can't find X without an additional information. X can take any value from 0 to 20.

Therefore Both propositions are NOT sufficient. Answer E

3. Good post? |
In short, just think ... what if no male has brown hairs
Bingo!! Solved

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