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crispyrat:

math help ss below

crispyrat:

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hailees3622:

Convert 11.42424242 … to a rational expression in the form of a over b, where b ≠ 0.

crispyrat:

i think you posted on the wrong question?

hailees3622:

i dont really know how to use this i jus need help on pre algebra

hailees3622:

hello?

crispyrat:

If you need help post ur own question

HighIQReptilian:

@hailees3622 wrote:
hello?
Hiya! Please look in the top left corner to find the ask a question button. Write your question and post. :D

crispyrat:

@highiqreptilian wrote:
@hailees3622 wrote:
hello?
Hiya! Please look in the top left corner to find the ask a question button. Write your question and post. :D
Don't forget to choose the correct subject :)

SmokeyBrown:

The question is asking "how many number of ways..." can this type of hand of cards be dealt. Well, we can walk through it manually to start, and maybe we'll start to notice a pattern. There are 13 different card "ranks" in total. We know that our hand will have 2 pairs (of different card ranks), and then the 5th card can be any of the remaining 11 ranks. We'll have a first pair, a second pair, and a lone card. The first pair can be any of the 13 ranks. The second pair can be any of the remaining 12 ranks. And the lone card can be any of the remaining 11 ranks. In general, that should mean that there are 13 * 12 * 11 ways to make that combination. I think, probability is not my strong suite.

crispyrat:

hmm i believe that i wrong because the fact that the order of cards doesn't matter so one would have tofind a way to get repeats out?

crispyrat:

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crispyrat:

so would I divide that by 13?

SmokeyBrown:

Oh good catch. You're right, with my method there would be repeats. Why divide by 13? I mean, that might be correct, I just don't understand.

crispyrat:

I wasn't sure it's just that i encountered a kinda similar problem and they divided by the base numbers

crispyrat:

@crispyrat wrote:
so would I divide that by 13?
I'm not sure that's the part im stuck in :(

SmokeyBrown:

Maybe I should try to work it out manually. Pairs of 2 can match with pairs 3 through Ace. So that's 12 pair combinations there. Then pair 3 can match with 4 through Ace. That's another 11 Pair 4 will give us another 10, pair 5 will give us another 9... Now the pattern is becoming clear. The pair-groups have 12+11+10+9+8+7+6+5+4+3+2+1 combinations. Then we can take that sum and multiply it by 11, to account for the lone card. And *that* should give us the total number of combinations.

SmokeyBrown:

I think that would be the original method I gave, divided by 2? I think that's what we had to do.

crispyrat:

ah that makes sense let me try that out!

crispyrat:

oh it was wrong?

SmokeyBrown:

I mean what I said before 13*12*11 was wrong. But this solution I just came up with should be correct, it's actually equal to (13*12*11)/2 Unless it's wrong again, in which case we can think about it some more.

crispyrat:

yea it was wrong again thats what i mean

SmokeyBrown:

Shoot. Alright, back to the drawing board I guess. Hmmmmm

SmokeyBrown:

Hold on, are we supposed to account for the suite of the card as well, like club, diamond, heart, spade? Because that would increase the different possibilities by a *lot*.

crispyrat:

i don't think so because it doesn't specfiy the suits in the example

SmokeyBrown:

Ok that's good. And we know the order doesn't matter, so we don't need to consider that... Just curious, what number did you get before from those calculations we tried?

crispyrat:

1716 and 858

SmokeyBrown:

Ok that's what I got too. Too bad it wasn't the answer. I wonder what it is we're missing here?

crispyrat:

maybe the overcounting part?

crispyrat:

we're dividing the wrong thing maybe?

HighIQReptilian:

If this is probability shouldn't we be doing 2/50 etc.?

HighIQReptilian:

Since we aren't putting cards back we also have to change the b of the probability fraction since the source is growing smaller

HighIQReptilian:

Aka, 4/52 * 3/52 * 4/52 *3/52 *4/44

HighIQReptilian:

The last one is 4/44 because we subtract the 2 ranks we have already pulled.

SmokeyBrown:

Oh hold on, the question is asking about "how many different ways can you be dealt 5 cards..." so we'd be looking for a whole number of combinations, not the fractional chance. It's a probability question, but not directly about probabilities

HighIQReptilian:

Huh, good point.

HighIQReptilian:

So really we should be looking at how many ranks there are

HighIQReptilian:

Which is 13

HighIQReptilian:

The chance of getting a card from one rank is 1/13

HighIQReptilian:

Then the next one would be 1/12 since it can't be the same rank. And the last would be 1/11

HighIQReptilian:

You would do the first two twice.

mhanifa:

Try this number: 56628

HighIQReptilian:

@mhanifa wrote:
Try this number: 56628
?????

crispyrat:

ah wait they are counting suits! my bad! but i found the answer already thanks for the help however

HighIQReptilian:

Suits? As in king queen?

crispyrat:

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SmokeyBrown:

@crispyrat wrote:
ah wait they are counting suits! my bad! but i found the answer already thanks for the help however
Oh awesome! No worries, I'm glad you figured it out, I was not looking forward to dealing with that lol

crispyrat:

answer if ur curios

HighIQReptilian:

I am very confused. Why are those numbers floating?

SmokeyBrown:

Thank you! That's actually quite informative, and not as complicated as I assumed

HighIQReptilian:

Are they being divided?

SmokeyBrown:

@highiqreptilian wrote:
I am very confused. Why are those numbers floating?
The floating numbers is a notation where you take the bottom number of combinations from the top number of options. So, floating 4 with a 2 under it means you make a combination of 2 choices out of 4 possible options (card suites, in this case)

HighIQReptilian:

Huh! Never heard of that! Thanks for the lesson @smokeybrown

SmokeyBrown:

Of course! I'm glad we can all learn together :)

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