A box contains 10 red pills 5 blue pills 12 yellow

Question

A box contains 
10 red pills
5 blue pills
12 yellow pills.


What is the least number of pills one must extract to ensure at least
1. one blue pill?
2. two blue pills?
3. one blue and one yellow?
4. two blue and one yellow?
5. two blue and two yellow?
6. at least one of each color?
7. at least 3 of each color?

walker · Accepted Answer

A box contains 
10 red pills
5 blue pills
12 yellow pills.


What is the least number of pills one must extract to ensure at least
1. one blue pill? 10+12+1=23
2. two blue pills? 10+12+2=24
3. one blue and one yellow? 10+12+1=23
4. two blue and one yellow? 10+12+2=24
5. two blue and two yellow? 10+12+2=24
6. at least one of each color? 10+12+1=23
7. at least 3 of each color? 10+12+3=25

srivas · Answer

A box contains
10 red pills
5 blue pills
12 yellow pills.

What is the least number of pills one must extract to ensure at least
1. one blue pill?
2. two blue pills?
3. one blue and one yellow?
4. two blue and one yellow?
5. two blue and two yellow?
6. at least one of each color?
7. at least 3 of each color?

Soln:
1. one blue pill?
Ans: The worst case is if we pick all 10 red pills and 12 yellow pills and then only pick the first blue pill. So the least number of pills to ensure that atleast one blue pill is taken is 23.

2. two blue pills?
Ans: Similar to first question. Since now we need two blue pills. Thus the answer is 24.10 red pills + 12 yellow pills + 2 blue pills

3. one blue and one yellow?
Ans: 10 red pills + 12 yellow pills + 1 blue = 23

4. two blue and one yellow?
Ans: 10 red pills + 12 yellow pills + 2 blue = 24

5. two blue and two yellow?
Ans: 10 red pills + 12 yellow pills + 2 blue = 24

6. at least one of each color?
Ans: 10 red pills + 12 yellow pills + 1 blue = 23

7. at least 3 of each color?
Ans: 10 red pills + 12 yellow pills + 3 blue = 25

JuliaS · Answer

On #3 - 7, why do you add 12 yellow instead of 5 blue? The question asks for the least number of pills to insure the combination. So, for example, for #3 - in order to ensure the least possible number of pills AND one blue and one yellow, can we have:

10 Red + 5 Blue + 1 Yellow = 16 total vs. 10Red + 12Yellow + 1Blue = 23 in the answer above

I applied the same approach to #4-7.

pmenon · Answer

Silly question, but arent the least number of pills, at least for question 1, one ? I.e. the first pill you pick is the blue one ??

bmwhype2 · Answer

these are worst case scenario problems. we want the max number of wrong pills before we get the correct pills.

we want to pull out the max number of other pills and then the correct pill in order to ENSURE that we get a correct pill.

JuliaS · Answer

So what is wrong with my approach on #3 then: 10 Red + 5 Blue + 1 Yellow = 16 ?

bmwhype2 · Answer

in order to ensure the correct pill,  we maximize the wrong ones

between yellow and blue, yellow has more pills. we choose all these before we choose blue.

neeraj.kaushal · Answer

Yeah in order to get least number of required ones , we need to maximise the wrong ones. 23 is right !

tejal777 · Answer

I found these uestions super cute!+ they are gr8 to clear one's concept!

pleonasm · Answer

So.. for 6 and 7 ..

At least one of each color .. since 5 is the lowest number we choose 10R 12Y and 1B ? I didn't quite get this.

eresh · Answer

The questions are tricky and fun at the same time.

I guess some are making confusing because of the wording. The question says

"What is the least number of pills one must extract to ensure at least"
So, we should consider the worst case scenario.

If the question would had asked 'What is the least number of pills one should extract to ensure one blue marbel and so and so...........
Then it might have been the best case scenario.....(I may be wrong

)

tashu · Answer

I think question should ask "MAX or Most" rather than "Least", for worst case scenario. 
What is the  max  number of pills one must extract to ensure at least ?

anil4410 · Answer

As tashu just pointed out, I also think the word "least" makes the whole question very ambiguous.

bonkers13 · Answer

One of my friend was asked a similar question in a job interview and he replied - "One" - interviewer asked how - and he said that "I am lucky so i will get it in first pick and would not wait for X picks (x=real solution))
Interviewer liked his boldness and presence of mind. And he was selected.

PiyushK · Answer

These questions are easy, but scares me allot as there is no direct formula to rely on or leave rest of the effort on well versed algorithms of addition subtraction or division, really it needs alert brain with no open holes in thought process to ignore any possibility or to miss any scenario. Its more like critical reasoning

Bunuel · Answer

Check similar questions to practice: 12-easy-pieces-or-not-126366.html#p1033935 in-his-pocket-a-boy-has-3-red-marbles-4-blue-marbles-and-85216.html of-the-science-books-in-a-certain-supply-room-50-are-on-131100.html in-a-deck-of-52-cards-each-card-is-one-of-4-different-color-83183.html a-box-contains-10-red-pills-5-blue-pills-12-yellow-56779.html each-of-the-integers-from-0-to-9-inclusive-is-written-on-130562.html a-student-is-asked-to-pick-marbles-from-a-bag-that-contains-72390.html of-the-science-books-in-a-certain-supply-room-50-are-on-131100.html if-a-librarian-randomly-removes-science-books-from-a-library-93861.html m10-q24-ps-69233.html#p1237169 each-of-the-integers-from-0-to-9-inclusive-is-written-on-130562.html Hope it helps.

Teslindo · Answer

For question 3, wouldn't the least amount be if you removed all red and all blue first to get at least 1 blue and 1 yellow? Meaning the least amount to ensure 1 blue and 1 yellow = 10 + 5 +1 ...?

Bunuel · Answer

For such questions you should consider the worst case scenario. The worst case scenario for question 3 (at least one blue and one yellow) would be if we pick all 10 red pills and all 12 yellow pills. In such case we still won't have at least one blue and one yellow. Next, pick however, would give us blue pill, so we would have at least one blue and one yellow. So, the correct answer is 10 + 12 + 1 = 23.

Check other  Worst Case Scenario Questions  in our  Special Questions Directory .

Hope it helps.

Yashvashisht17 · Answer

In the worst-case scenario, one could draw all 10 red pills and all 12 yellow pills, resulting in a total of 22 pills without obtaining a single blue pill. In this case, we would have at least three red pills and at least three yellow pills, but no blue pills at all. To ensure that there are at least 3 blue pills among the extracted ones, one must additionally draw 3 more pills, which would definitely be blue pills. Therefore, a total of 25 pills must be removed to guarantee that at least three pills of each color are among those taken out.

A box contains 10 red pills 5 blue pills 12 yellow

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A box contains 10 red pills 5 blue pills 12 yellow

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