What is the probability that a leap year will have 53 fridays?
A leap year has 366 days, therefore 52 weeks i.e. 52 Friday and 2 days.
The remaining 2 days may be any of the following :
(i) Sunday and Monday
(ii) Monday and Tuesday
(iii) Tuesday and Wednesday
(iv) Wednesday and Thursday
(v) Thursday and Friday
(vi) Friday and Saturday
(vii) Saturday and Sunday
For having 53 Fridays in a leap year, one of the remaining 2 days must be a Friday.
n(S) = 7
n(E) = 2
P(E) = n(E) / n(S) = 2 / 7
Thus, the required probability if 2/7.