What is the probability that a student randomly selected

Question

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.

hkm_gmat · Answer

Should be C 

1 = P(male) + P(brown) + P(neither male nor brown) - P(Both male & brown)

aikido_fudoshin · Answer

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?

cool_jonny009 · Answer

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

Bhai · Answer

E.

We need to know the number of males with brown hair.

ywilfred · Answer

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

andy_gr8 · Answer

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

BG · Answer

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)

chiragr · Answer

What would be level of this question I would guess 47+ any guess...

ps_dahiya · Answer

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

sperumba · Answer

Unfortunately Idon't have the OA for this question.

i thought One of you guys could help me out.

sorry about that.

bumpbot · Answer

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What is the probability that a student randomly selected

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