There have 12 basket,7 red balls and 5 white balls,find the probability of getting at least 1 red ball and 1 blue ball, if 8 balls are to be drawn ?

• 495...(7c3*5c5)+(7c4*5c4)+(7c5*5c3)+(7c6)5c2)+(7c1*5c1)=495
  
• 10 years agoHelpfull: Yes(29) No(18)
• We have to draw 8 balls. Suppose we draw 7 red balls initially. In order to take 8 balls out of the basket we have to obviously draw a blue ball. Let us take another case. Suppose this time we draw all the 5 blue balls, which means we need to draw three more balls which are obviously red.
  Hence there are always red and blue balls in the set when we draw 8 balls. Hence this is always true and the PROBABILITY in this case IS 1
• 10 years agoHelpfull: Yes(17) No(1)
• (7C6*5C2)+(7C5*5C3)+(7C4*5C4)=455
• 10 years agoHelpfull: Yes(14) No(12)
• 485
  7C7*5C1 + 7C6*5C2 + 7C5*5C3 + 7C4*5C4 + 7C3*5C5= 485
• 10 years agoHelpfull: Yes(10) No(4)
• 495/12c8
  =495/11880
  =11/264
• 10 years agoHelpfull: Yes(6) No(4)
• in 8 balls max red =7 and min=8-5=3
  and max blue=5 and min=8-7=1
  so probability=1........
• 10 years agoHelpfull: Yes(4) No(8)
• Is rhis site really helpful to crack Infosys written test?
• 10 years agoHelpfull: Yes(4) No(2)
• plz anyone explain how u solve question because in above qus. ask that at least 1 red and 1 blue ball but there is not given the number of blue ball so may be answere is 0
• 10 years agoHelpfull: Yes(3) No(1)
• we are asked to find the probability of getting at least 1 red ball and 1 blue ball, bt there is no blue ball, according to the question, so the probability of getting blue ball is zero, hence the probability of getting at least 1 red ball and 1 blue ball is also zero
• 10 years agoHelpfull: Yes(3) No(1)
• the question is asking about probability not the number of ways so,
  ans is 1
  n(s)= 12, n(E)= 7+5= 12
  P(E)= n(E)/ n(s) = 12/12 = 1
• 10 years agoHelpfull: Yes(2) No(0)
• there are 12 in basket :7 red and 5 white.
  PROBABILITY for atleast we use : 1-(all) i,e 1- { (7c7*5c1 ) +5c5*7c3)/12c8 }=455/495
  
  Is this a correct approach ??? ! please answer!
• 9 years agoHelpfull: Yes(1) No(0)
• they asked about probability,
  n(E) = (12 C 8)
  n(S) = (7 C 1)(5 C 1)
  hence ans = n(S)/n(E) = 35/495 = 0.7
• 10 years agoHelpfull: Yes(0) No(4)
• please explain!
• 9 years agoHelpfull: Yes(0) No(0)
• (7C6*5C2)+(7C5*5C3)+(7C4*5C4)=455
• 8 years agoHelpfull: Yes(0) No(0)
• in this question,we have find the probability not ways to drawing balls so the ans is 1.
• 8 years agoHelpfull: Yes(0) No(0)
• Total sample space==12C8=495
  probability of getting atleast 1 red and 1 white ball==4/495
• 6 years agoHelpfull: Yes(0) No(0)
• There are 12 balls, 7 red and 5 white.
  when 8 balls are drawn ,both red and white balls should be their to have 8 balls.
  so at least 1 red and 1 white is drawn in all possibility
  so ans is 1.
• 6 years agoHelpfull: Yes(0) No(0)