A box contains 8 Red, 16 Blue, 4 Yellow and 12 Black Balls.
One ball is picked up randomly. What is the probability that it is not Blue ?
1) 0.24
2) 0.8
3) 0.3
4) 0.5
5) None of these

• the probability that it is not Blue = 1-16/40 = 1-2/5 = 3/5 ... so none of these.
• 13 years agoHelpfull: Yes(23) No(0)
• The prob. of not getting a blue ball is;
  (40-16)/40=24/40
  or 0.6
  Ans: None of these
• 13 years agoHelpfull: Yes(7) No(2)
• In an alternative method,24/40=6/10=0.6
  24/40=>(8R+4Y+12black)/40
• 7 years agoHelpfull: Yes(0) No(0)