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sperumba
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What is the probability that a student randomly selected 16 Jan 2006, 11:10
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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.



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What is the probability that a student randomly selected 16 Jan 2006, 13:43
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Should be C

1 = P(male) + P(brown) + P(neither male nor brown) - P(Both male & brown)
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aikido_fudoshin
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What is the probability that a student randomly selected 16 Jan 2006, 14:06
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I am thinking E on this one. To find the probability of selecting a boy with brown hair from the class you need to know how many boys have brown hair. In this case you can find the probability that a boy will have brown hair but not the probability of selecting one from the group...... perhaps someone can clear this up for me?
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What is the probability that a student randomly selected 16 Jan 2006, 16:17
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E
(1) One-half of the students have brown hair.
We don't know how may male have brown hair. Could be all the brown hair stuents are women. INSUFF
(2) One-third of the students are males.
This tell how may are Male but no info about how many of them have brown hair INSFF

Taking togther ..
30 - Student with Brown Hair ( can be all women or 20 W + 10 M ....)
20 - Male students ( can have all brown hair or none ..) so Insuff

hence E
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Bhai
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What is the probability that a student randomly selected 16 Jan 2006, 18:07
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E.

We need to know the number of males with brown hair.
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ywilfred
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What is the probability that a student randomly selected 16 Jan 2006, 23:15
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1) Only know 30 students have brown hair. We can't tell the male:female makeup of these 30 students.

2) We know 20 students are male. Can't tell again.

Using 1) and 2), we know we have 20 male students, 40 females students. But we don't know out of these 20, how many have brown hair.

Ans E
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What is the probability that a student randomly selected 17 Jan 2006, 00:12
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E for me too

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.
we lknow p(b)=0.5 INSUFF
(2) One-third of the students are males.
we know only p(m)=0.33
but for combination to work we need to know p(neither males nor brown) which we dont know so INSUFF
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BG
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What is the probability that a student randomly selected 17 Jan 2006, 01:41
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the chance of selecting a student with brown hair is 1/2.
the chance of selecting a male student is 1/3
intersection of both is 1/6, then the prob of selecting a male student with brown hair is 1/6
so C)
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chiragr
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What is the probability that a student randomly selected 17 Jan 2006, 10:40
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What would be level of this question I would guess 47+ any guess...
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ps_dahiya
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What is the probability that a student randomly selected 17 Jan 2006, 15:34
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sperumba
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.


E

St1: No information about how many students are male. INSUFF

St2: No information about how many students have brown hair. INSUFF

Combined: 20 Students are male and 30 students have brown hair. We don't know how many male students have brown hair. INSUFF
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sperumba
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What is the probability that a student randomly selected 17 Jan 2006, 15:58
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Unfortunately Idon't have the OA for this question.

i thought One of you guys could help me out.

sorry about that.
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What is the probability that a student randomly selected 11 Jun 2017, 00:34
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