birthday prob

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birthday prob

by ruplun » Fri Jul 29, 2011 5:27 am
In a group of 8 persons what is the probability that at least 2 of them are born on the same day of the week?

a. 1/8
b. 1/7
c. 1/4
d. 1/2
e. 1
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by naveen451 » Fri Jul 29, 2011 9:17 am
IMO E

because there are only seven days a week

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by ruplun » Fri Jul 29, 2011 9:04 pm
plz explain

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by ntamhane » Fri Jul 29, 2011 9:40 pm
Mon Tue Wed Thrus Fri Sat Sun
P1 P2 P3 P4 P5 P6 P7
P8

If you try out any of such samples you will get minimum of 2 people born on the same day.

Hence Probability is 1 i.e E