Q. One lady has 2 children, one of her child is boy, what is the probability of having both are boys

• n(S)=one of her child is boy out of 2 children=BB,BG=2
  n(E)=both are boys=BB=1
  so p=n(E)/n(s)=1/2
• 10 years agoHelpfull: Yes(16) No(7)
• In a family with 2 children there are four possibilities:
  
  1) the first child is a boy and the second child is a boy (bb)
  
  2) the first child is a boy and the second child is a girl (bg)
  
  3) the first child is a girl and the second child is a boy (gb)
  
  4) the first child is a girl and the second child is a girl (gg)
  
  Since we are given that at least one child is a girl there are three possibilities: bg, gb, or gg. Out of those three possibilities the only one with two girls is gg. Hence the probability is 1/3.
• 10 years agoHelpfull: Yes(10) No(9)
• there are just two cases either both boys or one boy and one girl
  so prob= 1/2
• 10 years agoHelpfull: Yes(5) No(1)
• answer is 1/3
  because there is surely one boy. So the possibilities are bg,gb,bb
  
  the probability of having both boys : 1/3
• 9 years agoHelpfull: Yes(2) No(4)
• one is boy(given).
  So other one is either boy or girl.So (1/2) is the prob for both boys.
• 9 years agoHelpfull: Yes(2) No(0)
• possibilities are bb, bg , gb so bb is 1/3
• 8 years agoHelpfull: Yes(0) No(1)