There are two box,one containing 39 red balls and the other containing 26 green balls. You are allowed to move the balls between the boxes so that when you choose a box at random and a ball at random from the chosen box, the probability of getting a red ball is maximized. This maximum probability is
.60
.50
.80
.30

• 0.7968
  
  1/2(1+38/64)
• 14 years agoHelpfull: Yes(44) No(4)
• Here we are allowed to transfer the balls between the two boxes, so we keep only one red ball in first box and move all the remaining balls to the second box, so that we get maximum probability of drawing red ball from first box
  So first box--- only one red ball
  second box--- 38 red and 26 green
  Probability of choosing any box is 1/ 2.
  probability of choosing the red ball from first box is 1
  probability of choosing the red ball from second box is 38/64
  So probability of taking one red ball = [(1/2)×(1)]+[(1/2)*(38/64)]≃0.8
  
• 12 years agoHelpfull: Yes(23) No(1)
• Follow the process in puzzle #M40000963
• 14 years agoHelpfull: Yes(10) No(5)
• (1/2)*(1)+(1/2)*(38/64)=.6
• 14 years agoHelpfull: Yes(5) No(17)