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From the question stem, we are able to get the following details
1. Each sealed packet has a marker - Red, Blue, Or Black(which we can't see from outside)
2. 23 of the 40 packets have a black marker. Therefore, Blue + Red = 17

1. Statement 1 tells us that Blue < Red
Case 1: Red = 13, Blue = 4
Case 2: Red = 10, Blue = 7
Case 3: Red = 9, Blue = 8
We cannot come to a unique value for the number of packets containing Blue markers (Insufficient)

2. If he needs to withdraw 20 markers to have 8 of a color,
2 cases are possible such that 8 markers of either color can be taken out.
Case 1: Red = 12, Blue = 5
Case 2: Red = 5, Blue = 12
We cannot come to a unique value for the number of packets containing Blue markers (Insufficient)

Combining the information from both the statements,
the only option possible is Black = 23, Blue = 5, Red = 12 (Sufficient - Option C)
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aserghe1
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2. If he needs to withdraw 20 markers to have 8 of a color,
2 cases are possible such that 8 markers of either color can be taken out.
Case 1: Red = 9, Blue = 8
Case 2: Red = 8, Blue = 9
We cannot come to a unique value for the number of packets containing Blue markers(Insufficient)

What if Josh selects 7 black, 7 blue, 6 red? In that case, he will not have 8 markers of any one color.

Here's what I did...
40 packets
23 of them have black markers
(# of packets with red markers) + (# of packets with blue markers) = 17
We're asked to find the # of packets with blue markers.

Statement 1
(# of packets with blue markers) < (# of packets with red markers)
We can have (7 blue, 10 red), or (6 blue, 11 red).
Insufficient

Statement 2
This means that when Josh selects 19 packets, he is not guaranteed to have 8 packets of any one color. In the worst case scenario, Josh will select 7 packets of one color, 7 packets of another, and 5 packets of another color (total selected = 19 packets). The 20th packet he selects MUST give him 8 packets of one color, thus one of the colors must have 5 packets. So we either have (5 red, 12 blue) or (12 red, 5 blue).
Insufficient

Combine Statements 1 & 2
Per Stmt 1: red < blue
Per Stmt 2: (5 red, 12 blue) or (12 red, 5 blue)
Combined, we get 5 red, 12 blue

Answer: C



Have corrected my solution. Thanks for noticing aserghe1

I mistook the question "he needs to draw minimum 20 packets to ensure that he has exactly
8 markers of any single color out of red, blue, black." and thought it meant that he could take
8 of any color. But as you rightly pointed out there is a possibility that he may not have 8 of
either color if I used the numbers for markers: Black - 23, Red - 8, Blue - 9
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Why are considering Combinations of (12 & 5) only ?
Why it can't be (11&6) or (10&7)
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pushpitkc
From the question stem, we are able to get the following details
1. Each sealed packet has a marker - Red, Blue, Or Black(which we can't see from outside)
2. 23 of the 40 packets have a black marker. Therefore, Blue + Red = 17

1. Statement 1 tells us that Blue < Red
Case 1: Red = 13, Blue = 4
Case 2: Red = 10, Blue = 7
Case 3: Red = 9, Blue = 8
We cannot come to a unique value for the number of packets containing Blue markers (Insufficient)

2. If he needs to withdraw 20 markers to have 8 of a color,
2 cases are possible such that 8 markers of either color can be taken out.
Case 1: Red = 12, Blue = 5
Case 2: Red = 5, Blue = 12
We cannot come to a unique value for the number of packets containing Blue markers (Insufficient)

Combining the information from both the statements,
the only option possible is Black = 23, Blue = 5, Red = 12 (Sufficient - Option C)

Not certain how statement 2 results to Options of 12R,5B or 12B, 5R. Can it not be 11R,6B or 11B,6R this option also agrees to the statement of 8 of any one color. What am i missing here ?
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Hello VeritasKarishma
Can you please help me out with this question ?
I'm not understanding how from the second condition we can assume the below
Case 1: Red = 12, Blue = 5
Case 2: Red = 5, Blue = 12
I saw a similar question in Veritas question bank.
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Anush56
Hello VeritasKarishma
Can you please help me out with this question ?
I'm not understanding how from the second condition we can assume the below
Case 1: Red = 12, Blue = 5
Case 2: Red = 5, Blue = 12
I saw a similar question in Veritas question bank.

From the second statment you can conclude that red or blue must be 5.
If red or blue could be 6 then the second statment would be false because choosing 20 packets the combination black:7, red:7 and blue:6 would be possible and you does not have 8 markers of a single coluor.
We can also conclude that red or blue can not be 4 because the minimum would be 19 packets and not 20 as the statment says.
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VeritasKarishma
Anush56
Hello VeritasKarishma
Can you please help me out with this question ?
I'm not understanding how from the second condition we can assume the below
Case 1: Red = 12, Blue = 5
Case 2: Red = 5, Blue = 12
I saw a similar question in Veritas question bank.


Think of it this way -

Stmnt 2 tells you that you need to withdraw 20 markers to ensure that you have at least 8 of the same colour.

So this means that you could pick 19 markers and still not have 8 of the same colour. But when you pick the 20th, you MUST have 8 of a colour.

So then, worst case scenario, how many of what colour markers could this 19 be such that the 20th has to ensure that you have 8 markers of 1 colour, no matter which marker you pick next?
We would assume that this happens in case we have 7 markers of all colours so that when we pick the next marker, it gives us 8 of one of the colours but that is not possible since we have only 19 markers. This means we must have total only 5 markers of one colour and 7 of the other two to make up 19. Now the leftover markers would only be of the other two colours. So whichever marker we pick next, it will give us 8 of one of the two other colours.

Since we know there are 23 black markers, it means we have only 5 markers of either red or blue.
If we have 5 red markers, then we have total 12 blue markers.
If we have 5 blue markers, then we have total 12 red markers.
Either case is possible.

Thank you so much ! This helps a lot. I find Min/ Max problems always tricky and addition when the question relates to maximizing or minimizing a certain quantity makes it all the more stressful.
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Prompt:
Let Black=B, Blue=E, Red=R

B+E+R=40
B=23

This gives us

E+R = 17

We need to find E

1) E < R. Insufficient. (E,R) can be (1,16),(2,15) and so on.
2) Start with worst case scenario, you end up with 7 of each color. If this is the case, then you need to draw 22 pens (7 of each color, to guarantee next marker will be the 8th of a color). We however only need to draw 20. This means we we have either:

7+ = 7 or more

7+, 6, 6 (draw 12 from the two colors with 6 markers each, 7 from the 7+ color, and you're guaranteed 8th of the 7+ color on the 20th draw)
or
7+, 7+, 5 (draw 5 of the color with 5 markers, 7 from each of the 7+, then 20th marker is 8th of either of the 7+ colors)

Black is 23, so it's one of the 7+
This means 7+,6,6 combination is impossible because 6+6= 12 !=17 that we need for E+R

(E,R) can be (12,5) or (5,12)

2) is insufficient

Combine 1) and 2) and we see (E,R) = (5,12) and we have 5 blue markers.

Answer: C
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KarishmaB
Anush56
Hello VeritasKarishma
Can you please help me out with this question ?
I'm not understanding how from the second condition we can assume the below
Case 1: Red = 12, Blue = 5
Case 2: Red = 5, Blue = 12
I saw a similar question in Veritas question bank.


Think of it this way -

Stmnt 2 tells you that you need to withdraw 20 markers to ensure that you have at least 8 of the same colour.

So this means that you could pick 19 markers and still not have 8 of the same colour. But when you pick the 20th, you MUST have 8 of a colour.

So then, worst case scenario, how many of what colour markers could this 19 be such that the 20th has to ensure that you have 8 markers of 1 colour, no matter which marker you pick next?
We would assume that this happens in case we have 7 markers of all colours so that when we pick the next marker, it gives us 8 of one of the colours but that is not possible since we have only 19 markers. This means we must have total only 5 markers of one colour and 7 of the other two to make up 19. Now the leftover markers would only be of the other two colours. So whichever marker we pick next, it will give us 8 of one of the two other colours.

Since we know there are 23 black markers, it means we have only 5 markers of either red or blue.
If we have 5 red markers, then we have total 12 blue markers.
If we have 5 blue markers, then we have total 12 red markers.
Either case is possible.

Why Is this case not possible Red=9, blue 8 which adds to 17 and balance 3 markers are picked up from 23 black markers?
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