In a jar there are 15 white balls, 25 red balls, 10 blue balls and 20

Thats 29 in C.

I love these types of questions..

I don't get why there will be 7 of each when we draw out 28 balls. Could you please elaborate?

Arora2m this one is for you :

Black Blue Yellow Green
1 1 1 1
1 1 1 1
.
.
.
.
.

similar pattern 7 times. the next ball will have to be from either of the colors and making the total tally of that color to 8 balls

HI where do we come across these type of questions in og 11.If you could point out the question numbers it will be really greatful asap.

nice question.

take 7 out of each color.7*4 + 1 = 29

Can someone please elaborate the concept in this question. Why do we have to consider each ball of different color??

This is a very simple question.
Jar contains 15 WB, 25 RB, 10 BB, 20 GB.

Now to ensure that there must be 8 balls of same colour,
the best case will be, we take out 8 ball of same colour &
the worst case will be when we take out 7 balls of each colours and then we take out any ball.
The last ball's colour will be the colour of the 8 balls with same colour and other 7 balls will be of their respective colour.

So to ensure that we have 8 balls of same colour we need to take out 7+7+7 +8 = 29 balls.

Answer C.

The worst case scenario would be having to draw 7 balls of each color so that we wouldn’t have 8 balls of any one color. However, if we were to remove just one more ball, regardless of the color, we would then have 8 balls of one color. Thus, we need to remove 7 x 4 + 1 = 29 balls.

Answer: C

The maximum we can take out before we have 8 of the same color is 7 of each color.

7 * 4 = 28

Then any additional ball we take will complete a set of 8.

So 29

Answer choice C

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The minimum we need 7 balls for each color.[White, Red, Blue, Green]

=> 7 + 7 + 7 + 7 = 28.

The next ball will be of either of the color [White, Red, Blue, Green] and when added to 28 will make 8 balls of the same color for any color.

=> 28 + 1 = 29

Answer C

I believed there was some underlying trick I was missing.....


We have:

White..................Red.....................Blue.......................Green
15.......................25.......................10..........................20


We need to keep pulling balls out blindly. How many balls do we need to pull out such that in every possible scenario we MUST have 8 balls of the Same color?


Worst luck in the world:

1st) we pull out 7 White

2nd) we pull out 7 Red

3rd) we pull out 7 Blue

4th) we pull out 7 Green
_________________________

at this point we have pulled out 28 Balls and we do NOT have 8 balls of the same color.


On our next pull, not matter which color we pull, it will complete a Series of 8 Identical Colors.


29 Pulls of Balls guarantees that we will have 8 balls of the same color


Answer: 29

-C-

Does anyone have list links that are similar to this question?

Thanks in advance!

It's already given above.

Check other Worst Case Scenario Questions from our Special Questions Directory to understand the concept better.

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