in a room there are 7 person,the chance that two of them were born on the same day of the week is.

• first select two person from 7 in 7C2 ways.
  select a day which they have to be born in 7C1 ways.
  for the remanning 5 people select 5days out of 6days of week and no. of arrangment of these 5 people in 5 days = (7C2*7C1*6C5*5!)ways.
  also,7 people born on 7 days whould be 7^7
  hence
  (7C2*7C1*6C5*5!)/(7^7) =2160/7^5
• 9 years agoHelpfull: Yes(1) No(0)
• ans is 7c2*7/5040=147/1716=49/572
• 9 years agoHelpfull: Yes(0) No(0)