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anonymous
 5 years ago
An urn contains 7 white balls and 3 red balls. Three balls are selected. In how many ways can the 3 balls be drawn from the total of 10 balls
a) If 2 balls are red?
b) If 3 balls are red and 2 are white?
c) If at leas 4 are red balls?
anonymous
 5 years ago
An urn contains 7 white balls and 3 red balls. Three balls are selected. In how many ways can the 3 balls be drawn from the total of 10 balls a) If 2 balls are red? b) If 3 balls are red and 2 are white? c) If at leas 4 are red balls?

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm trying to understand the problem.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I suppose I have to use combinations.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1me too are we taking out 3 or more?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1it says 3 but then talks about if 4 are red...

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1so for the first are we assuming that 2 of the 3 we are taking out are red or...?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I guess. But if that is the case then I need to use a permutation.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1that's what I'm confused on if the first question is asking 'we draw 3 balls, how many ways can we do this of two of the three we take out are red?' then I would say 3 ways to select red balls 7 ways to select the white ball 3*7=21 but then what about the rest?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1that's if the balls are unique of course^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0No they are not unique.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1oh, well then I'm really confused. I especially don't see how you can have 4 red balls when it says there are 3 in the urn..:/

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I made a mistake. I copy part of the problem below the one i wanted.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0b) If all 3 balls are white.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0c) If all 3 balls are red=

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1well I still don't get the question. if it is as I said above and the balls are not unique, then...no I'm lost, sorry

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well at least I'm don't feel alone with the problem =)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I really want to understand this counting techniques.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1lol I'll be interested to see if someone understands it. Buena suerte!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I think you were right TuringTest. They can be called: red_1, red_2, red_3, etc.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0In that case I'm selecting 2 out of 7 white balls and 1 out of 3 red balls. So.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[C(7,2)\cdot C(3,1)\]

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I though the first was 2 red balls and one white

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1does the order that we pull them out in matter? I guess it should, so my above answer is wrong.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0a) If2 balls are white and 1 is red.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0The order matters, otherwise I'm lost.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1yes, otherwise the answer to c) is 1

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Tu sabes español verdad T

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1well c) should still be the easiest: 3!=6

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1on poco tengo que hacer la tarea para miercoles. no hice nada en lalas vacaciones! estas de acuerdo conmigo acerca parte c) ?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ahh. What do you think about this: I help you with your spanish, and you can help me with my english.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1your english is a lot better than my spanish I'm going to school here taking language classes do you agree about part c?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I think the answer to c) is 1

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1only if the order doesn't matter

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1if it does then it is 6 do you want me to convince you?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Are you sure the order matters?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I'm going to draw some circles to represent the balls lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well Hero sometimes help with my english. Hi write something to him and he says: "No, you can write that in this way". I'm very grateful to him, but I'm ashamed that I can't not help him with something I know.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I was wondering if I can ask you similar things, and I can help you if you have spanish doubts.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well even if you can't help me, you can always ask me if you have some doubts.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1"can't not help him" should be "can't help him" and I your the first mexican I've met who actually wants to help. All my friends just make fun of me. anyhow I see 6! ways te select 2 white balls out of 7

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I meant 6+5+4+3+2+1=21 ways to select the two white ones

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0But if the order matters It should be a permutation, so P(7,2) is not equal to 6! I think.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1no, I was wrong about that sorry my working theory is that the order does not matter and that there are 21 ways to select 2 white balls out of seven, and 3 ways to select the red one for each of those, so 21*3=63 ways for part a) make any sense?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yes! that makes sense!

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1ok then let's see if I have anything for b)...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I thought about selecting 3 whites out of 7, so C(7,3) = 35

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1well so then the answer is a)63 b)35 c)1 IF the order of selection does not matter. so what if it does???

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Mmm good question, I'm thinking about it.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I don't think I know how to do those.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So you think this problem is done?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0That would be great! hehe

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I think you probably know better. Where did you get this problem? Does it seem like it should be so difficult as to have to consider order? That seems extraneous to me, unless you have an advanced combinatorics book or something.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It is from the book: "College Algebra" written by Sullivan. It seems isa High School book.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1Then I think we are done :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Thank you =). And what do you have to do for homework?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I'm trying to figure out what my girlfriend just texted me... chulos ojos de perrito enamorado not sure what enamorado means, but it must be enamored, eh? I have to do adverbs, practice past participle, negations, and... I don't know. A lot. I should have done it over break.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0enamorado means to be in love.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1awww well that's almost what enamored means

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I finished my credits at college, I hope to get my undergraduated grade this year.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Mechatronics Engineering

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I don't understand quite well what you mean with enamored. Does that word exist in english?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1Dang, what math did you have to take for that? I would think a lot, but it seems like you don't know too much more than me.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1enamored means obsessed basically, but the word doesn't mean something quite as bad as obsessed

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ahh so you were almost right.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1or 'awestruck' like I'm enamored by the presence of somebody special so almost...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0well I took the basics matehmatics, Algebra, Linear Algebra, Analytic Geometry, Calculus, Probability(Even it seems I didn't), Differential Equations, Complex Analisys, etc.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0yes, How did you know?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1because that's where I want to go

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1and you told me you lived in DF

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ohh, want do you want to study there?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1Whatever the highest physics I can get into is.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I mispelled something, nevermind. So you want a physic's PhD, at UNAM.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1If I can. I don't know how they feel about gringos getting in though. But UGDL sucks.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0So you are studying at UGDL right now.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1Just two classes. Between that, moving here, and language I'm busy. It's just a bad system in my opinion. They don't have high enough standards.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You mean academic standars, or administrative standars?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1academic was what I meant, but I'm sure administrative as well. My girlfriend had 4/6 of her graphic design teachers be about 25 years old. I'm almost that old! Not exactly tenure...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well the teachers here are very old hehe.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0but there is a good academic level too.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0But I think that the best option is at Cinvestav, have you heard of it?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0It's has several (places?) on the country, Queretaro, D.F, I'm not sure if Guadalajara.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I'll look into it. wrote the name down

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0There you can find the best academic level in the country.It is difficult to get in.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1brief english lesson: It's has several (places?) on the country It has several locations in the country ^^^correct

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ohh thank you, that is what i meant with my bad english!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0There is a Guadalajara's Cinvestav.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I wish you could just give me little tips like that in spanish, but I've only been taking classes for 2 1/2 months. It'll be awhile befor I'm fluent :( there is?!?!?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Don't worry feel free to write in spanish. That is the best way to learn, by practicing

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1Thanks for not laughing at me... or at least thanks for not writing lol!! what 'there is'? where

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1oh mine that was to your last comment about there being a school here I went 'there is?" out of surprise

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Don't worry =P. I was telling you that there is a Cinvestav located on Guadalajara.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You can take a look here: http://www.cinvestav.mx/posgrado.aspx

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Does you gf speaks english?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I even have some of the (admission or entrance?) exams. Let me see..

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1Yeah, which has really slowed me down. She has no patience. Everytime I ask her something she says 'that's stupid, why would you ask that?' I will be looking into that school here, I kinda like Guadalajara, and after living in LA for 12 years I don't really want to move to DF more expensive to, right?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1cool! entrance exam is the term, what is it in spanish?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Examen de admisión. That is the reason I get confused.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1right, I tried to say pagar atencion once, I got laughed at, but that's what it is in english "pay attention" not "put attention"

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1again sorry for not having accent marks...

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Don't worry 70% of mexicans don't know how to use the accent marks.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0But is good that you learn how to use them.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1My roomate spoke spanish at home all his life and was born in DF, but I correct him on things sometimes because I'm learning spanish formally. He never did that.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You mean your roomate at LA?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I think we have the same time zone, right? I know it's not that late, but I think I should try to sleep. I have to do 2 weeks worth of homework tomorrow =(

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Yeah, it's better to go to sleep. I'm still looking for the entrance exam.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1Thanks for the info on Cinvestav, I'll look into it. And looking for the exam. If you find it I'd be curious to hear what it has.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Ok, Have a good night, I'm goint to be here tomorrow in case you need some help.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1I may have to take you up on that, thanks! goodnight NoData.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0what does it means to take something up?

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1"to take someone up on an offer" I said I'd have to take you up on your offer, meaning I may ask you for help with spanish.

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1or just, 'I might take you up on that' for short

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well is difficult to learn that in a book or with google traslator. thank you so much. And have a good night again

TuringTest
 5 years ago
Best ResponseYou've already chosen the best response.1yeah expressions are tricky... goodnight :D
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