Sample space probability
Assume that the probability that a person is born on any given day is $dfrac{1}{365}$ (ignoring February $29$). In a group of $100$, what is the expected number of sets of two people that have the same birthday? What is the sample space?
I am a bit confused for that question, any thoughts? thanks!
probability
edited Nov 27 '18 at 16:35
amWhy
191k28224439
asked Nov 27 '18 at 16:28
Laura1999
202
add a comment |
Assume that the probability that a person is born on any given day is $dfrac{1}{365}$ (ignoring February $29$). In a group of $100$, what is the expected number of sets of two people that have the same birthday? What is the sample space?
I am a bit confused for that question, any thoughts? thanks!
probability
edited Nov 27 '18 at 16:35
amWhy
191k28224439
asked Nov 27 '18 at 16:28
Laura1999
202
add a comment |
Assume that the probability that a person is born on any given day is $dfrac{1}{365}$ (ignoring February $29$). In a group of $100$, what is the expected number of sets of two people that have the same birthday? What is the sample space?
I am a bit confused for that question, any thoughts? thanks!
probability
edited Nov 27 '18 at 16:35
amWhy
191k28224439
asked Nov 27 '18 at 16:28
Laura1999
202
Assume that the probability that a person is born on any given day is $dfrac{1}{365}$ (ignoring February $29$). In a group of $100$, what is the expected number of sets of two people that have the same birthday? What is the sample space?
I am a bit confused for that question, any thoughts? thanks!
probability
probability
edited Nov 27 '18 at 16:35
amWhy
191k28224439
asked Nov 27 '18 at 16:28
Laura1999
202
edited Nov 27 '18 at 16:35
amWhy
191k28224439
asked Nov 27 '18 at 16:28
Laura1999
202
edited Nov 27 '18 at 16:35
amWhy
191k28224439
edited Nov 27 '18 at 16:35
amWhy
191k28224439
edited Nov 27 '18 at 16:35
amWhy
191k28224439
191k28224439
asked Nov 27 '18 at 16:28
Laura1999
202
asked Nov 27 '18 at 16:28
Laura1999
202
asked Nov 27 '18 at 16:28
Laura1999
202
202
add a comment |
add a comment |
1 Answer
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HINT
Let $B$ be a discrete uniform random variable, with values in $[1,2,3,ldots,365]$. Each person's birthday is then one of these.
You have a group of $n$ people, and hence $n$ independent birthdays $B_1, B_2, ldots, B_{100}$. How many pairs $(i,j)$ can you find that $B_i=B_j$?
answered Nov 27 '18 at 16:32
gt6989b
33k22452
add a comment |
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1 Answer
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active
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votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
HINT
Let $B$ be a discrete uniform random variable, with values in $[1,2,3,ldots,365]$. Each person's birthday is then one of these.
You have a group of $n$ people, and hence $n$ independent birthdays $B_1, B_2, ldots, B_{100}$. How many pairs $(i,j)$ can you find that $B_i=B_j$?
answered Nov 27 '18 at 16:32
gt6989b
33k22452
add a comment |
HINT
Let $B$ be a discrete uniform random variable, with values in $[1,2,3,ldots,365]$. Each person's birthday is then one of these.
You have a group of $n$ people, and hence $n$ independent birthdays $B_1, B_2, ldots, B_{100}$. How many pairs $(i,j)$ can you find that $B_i=B_j$?
answered Nov 27 '18 at 16:32
gt6989b
33k22452
add a comment |
HINT
Let $B$ be a discrete uniform random variable, with values in $[1,2,3,ldots,365]$. Each person's birthday is then one of these.
You have a group of $n$ people, and hence $n$ independent birthdays $B_1, B_2, ldots, B_{100}$. How many pairs $(i,j)$ can you find that $B_i=B_j$?
answered Nov 27 '18 at 16:32
gt6989b
33k22452
HINT
Let $B$ be a discrete uniform random variable, with values in $[1,2,3,ldots,365]$. Each person's birthday is then one of these.
You have a group of $n$ people, and hence $n$ independent birthdays $B_1, B_2, ldots, B_{100}$. How many pairs $(i,j)$ can you find that $B_i=B_j$?
answered Nov 27 '18 at 16:32
gt6989b
33k22452
answered Nov 27 '18 at 16:32
gt6989b
33k22452
answered Nov 27 '18 at 16:32
gt6989b
33k22452
answered Nov 27 '18 at 16:32
gt6989b
33k22452
33k22452
add a comment |
add a comment |
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