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What is the probability of selecting zeroes from odd rows an

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YMAkib
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What is the probability of selecting zeroes from odd rows an [#permalink] New post   Updated on: 03 Apr 2019, 09:46
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What is the probability of selecting zeroes from odd rows and odd columns?

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\(\frac{1}{2}\)

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Originally posted by YMAkib on 14 Dec 2018, 01:29.
Last edited by Carcass on 03 Apr 2019, 09:46, edited 2 times in total.
Edited by Carcass
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chetan2u
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   14 Dec 2018, 15:12
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YMAkib wrote:
What is the probability of selecting zeroes from odd rows and odd columns?


So here we are looking for only odd rows and odd columns.
If you see at an odd row, say 1 - it has one 0 and nine 1s whereas odd column 1 has opposite - one 1 and nine 0s.
Similarly for all other similar numbered rows and columns.
Hence the probability will be 50% or \(\frac{1}{2}\)
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akingba
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   26 Jan 2019, 12:41
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Odd Row 5/10
Odd Column 5/10
Both 1/2*1/2=1/4
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Darpan100
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   11 Mar 2019, 22:01
I think answer is wrong.
can you please check it again?
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   12 Mar 2019, 03:41
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which one do you refer to is wrong ??
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LT2018
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   03 Apr 2019, 09:19
OA?
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   03 Apr 2019, 09:46
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Added.

Regards
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   04 Oct 2019, 11:25
1/4
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   29 Jan 2020, 11:11
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I think the answer is not 1/2
lets call i the indice number of rows and j the indice number for columns.
As we are looking at the odd numbers, (i,j) are in [1,3,5,7,9].
Now the probability of getting a zero is the probability of having i>= j.
so the number of possibilities to get i>= j when chosing a couple of numbers is 5+4+3+2+1=15.
(if j=1, you have 5 choices, if j=3, you have 4 choices ...)
The number of possibilities is 5*5=25.
So the probability to get a zero is 15/25 = 3/5
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   29 Jan 2020, 12:15
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beckhamine wrote:
I think the answer is not 1/2
lets call i the indice number of rows and j the indice number for columns.
As we are looking at the odd numbers, (i,j) are in [1,3,5,7,9].
Now the probability of getting a zero is the probability of having i>= j.
so the number of possibilities to get i>= j when chosing a couple of numbers is 5+4+3+2+1=15.
(if j=1, you have 5 choices, if j=3, you have 4 choices ...)
The number of possibilities is 5*5=25.
So the probability to get a zero is 15/25 = 3/5



Yes! I think you are correct - also, nice explanation!

For those who did not get it, here is the diagram:

Attachment:
11.JPG
11.JPG [ 38.33 KiB | Viewed 3352 times ]


The shaded boxes are those that belong to odd rows and odd columns

There are 25 such boxes and the number of zeroes is 15

Hence, 15/25 = 3/5 should be the correct answer
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   12 Jun 2020, 20:53
@GreenlightTestPrep can you please explain?
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   13 Jun 2020, 05:47
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Farina wrote:
@GreenlightTestPrep can you please explain?


This is a very poorly-worded question.
To be honest, I'm not even sure what it's asking

What is the probability of selecting zeroes from odd rows and odd columns?
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Re: What is the probability of selecting zeroes from odd rows an [#permalink] New post   11 Jul 2021, 08:54
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