Posted by Heidi on Wednesday, July 9, 2014 at 4:32pm.
The probability the New Year's day is on Saturday is a randomly chosen year is 1/7.
15 years was chosen randomly. Find the probability that,
(1) Exactly four of these years have a New Year's day on a Saturday.
(2) At least two of these years have New Year's day on a Saturday.

Statistics/Probability  Reiny, Wednesday, July 9, 2014 at 5:19pm
prob(Saturday) = 1/7
prob(not Saturday) = 6/7
prob(exactly 4 of 15 years is a Saturday)
= C(15,4) (1/7)^4 (6/7)^11
= appr .1043
at least 2 Saturdays > 1  (case of 0 Saturday + case of 1 Saturday)
= 1  (6/7)^15  C(15,1)(1/7)(6/7)^14
= .6534
check my arithmetic
Answer This Question
Related Questions
 Math  a probability that new years is on a Saturday in a randomly chosen year ...
 What is the probability that a randomly  Here is the probability model for the ...
 Probability  If three people are randomly selected, find the probability that ...
 Statistics  A life insurance company sells a term insurance policy to a 21year...
 Probability  A large governmental survey of dental care among children 2 to 17 ...
 finite math  The probability that a 3year old garter snake will reach 4 years ...
 finite math  The probability that a 3year old garter snake will reach 4 years ...
 finite math  The probability that a 3year old garter snake will reach 4 years ...
 I am having trouble with this homework question ,  Here is the probability ...
 statistics  According to a certain country's department of education 39.6% of 3...
More Related Questions