In the set{1,2,3,4,5} any 3 random number choosen can be same numbers wat is the probability so tat a*b+c is even

• given set is 1,2,3,4,5
  our aim is to find probability so that a*b+c should be even
  a*b+c gives even number when two odd numbers is added
  i.e, odd no+odd no gives even no.
  and even no + even no gives even no
  so lets consider case1:odd+odd=even (a*b) is odd and c is odd
  now a*b gives a odd no when a and b are odd no.
  probability of odd number from given set=3 by 5
  so case1 gives the prob as (3 by 5)*(3 by 5)*(3 by 5)=(27 by 125)........1
  
  case2: even+even=even
  prob of even no from the set=2 by 5
  a*b is even and c is even (three cases are possible)
  a(odd) b(even) c(even)= (3 by 5)*(2 by 5)*(2 by 5)and
  a(even) b(odd) c(even)= (2 by 5)*(3 by 5)*(2 by 5)and
  a(even) b(even) c(even) = (2 by 5)*(2 by 5)*(2 by 5).
  so totally (27+12+12+8)by 125......ans
  
• 12 years agoHelpfull: Yes(35) No(1)
• 59/125....
• 12 years agoHelpfull: Yes(6) No(1)
• ans=59/125
  
• 12 years agoHelpfull: Yes(2) No(1)
• even+even=even
  odd+odd=odd
  (2*2+2)=6
  (3*3+3)=12 des r choices
  total ways of selecting=5*5*5=125
  total ways =18/125
• 12 years agoHelpfull: Yes(1) No(13)
• ans is 47/125
• 12 years agoHelpfull: Yes(1) No(4)