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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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?
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga.
Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.
Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
that'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?
Well 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.
"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
no, 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?
I 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.
I'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.
well I took the basics matehmatics, Algebra, Linear Algebra, Analytic Geometry, Calculus, Probability(Even it seems I didn't), Differential Equations, Complex Analisys, etc.
academic 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...
I 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?!?!?
Yeah, 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?
My 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.
I 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 =(