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A bag contains 64 balls of 8 diff colors.There are eight of each color (including red).what is tha least number u hav to pick,with out looking ,to be sure of selecting 3 red balls
Read Solution (Total 12)
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- 8C3/64C3
selecting 3 out of 8 red balls so 8C3
total possibility is 64C3 - 11 years agoHelpfull: Yes(27) No(5)
- 59
total balls = 64
red balls = 8
now being sure of 3 red balls means (8-3)balls is to be present in the bag
so 64-5=59 - 11 years agoHelpfull: Yes(25) No(7)
- I THINK 59 BALLS
(BCZ,WE WANT 3 RED BALLS OUT OF 8 BALLS 3 NEED TO CHOOSE SO FOR 56 ATTEMPTS ALL COLORED BALLS CAME +3 ATTEMPTS BRING 3 RED BALLS SURELY) - 11 years agoHelpfull: Yes(14) No(1)
- total balls 64..8 diff colors means ,each color has 8 balls
8*8=64
similarly we have 8 red balls
now have to pick 3 red balls
possibility of 3 red balls= 8C3/ 64C3= 1/744(probability) - 11 years agoHelpfull: Yes(5) No(1)
- ans is 59
taking the worst case scenario: getting pattern of 7 diff. color balls(not red)..
this pattern repeats 8 times so 56 next we get 3 balls red simultaneously so 56+3 is 59
- 11 years agoHelpfull: Yes(3) No(0)
- 59 balls
59 is the least number of balls u hav to pick, with out looking ,to be sure of selecting 3 red balls. - 11 years agoHelpfull: Yes(2) No(1)
- clearly 59 is the no of attempts we require for getting out 3 red balls
and probability for getting same is 8c3/64c3 - 10 years agoHelpfull: Yes(2) No(0)
- 59 is ans..
- 10 years agoHelpfull: Yes(1) No(0)
- total balls=64
among 8 red balls we have to pick atleast 3
so we without considering other colors we can leave 5 balls in the bag so we can get toatal 7 types of colored balls and three balls of remaining type....
So we can pick 64-5=59 balls
we can get minimum 3 red balls - 11 years agoHelpfull: Yes(0) No(1)
- here it is clearly written that 8 balls of diff color including red
- 11 years agoHelpfull: Yes(0) No(0)
- answer is---13/39
- 11 years agoHelpfull: Yes(0) No(2)
- i think the ans will be 17 because when we pic 2 ball's of each color then the steps will be 16 , now when in 17th step the ball be red.
- 9 years agoHelpfull: Yes(0) No(0)
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