getcalc.com's Probability calculator to find what is the probability of 53 Fridays in a non-leap year. The ratio of expected event to all the possible events of a sample space for 1 odd day to be Friday is the probability of getting 53 Fridays for a non-leap year.
P(A) = 1/7 = 0.14
Users may refer the below detailed information to learn how to find the probability of 53 Fridays in an ordinary year. The total number of weeks in a non-leap year {365 days = 52 (1/7)} is 52 weeks and one odd day. Since, finding the probability for an odd day to be Friday is enough to find the probability of getting 53 Fridays in an ordinary year of a Gregorian calendar.
Workout
step 1 Possible events for 1 odd day
The odd day may be either Sunday, Monday, Tuesday, Wednesday, Thursday, Friday or Saturday. Therefore, the total number of possible outcome or elements of sample space is 7.
step 2 Probability of 1 Odd day to be Friday :
The sample space S = {Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday}
Expected event of A = {Friday}
P(A) =
{Friday}/{Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday}
P(A) = 1/7
P(A) = 0.14
0.14 or 1/7 is probability for 53 Fridays in a non-leap year.