PROBABLY PROBABILITY!!
Once I called 6 of my friends to my birthday party. So, what is the probability of finding two of them being born in the same month?
Directions:
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Just consider the first two digits after the decimal. (if you get 0.222800925 as answer, just consider 0.22)
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You must give the answer in decimals up to two decimal places!!
The answer is 0.78.
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1 solution
As I have called 6 of my friends to my birthday party, we will first count the probability of no one being born in the same month!
Thus, my 1 s t friend has 1 2 1 2 probability since it has the freedom to take birth in any month.
well, my 2 n d friend has 1 2 1 1 probability since it has the freedom to take birth only in any remaining 11 months.
.......
.......
.......
similarly as we carry down the process we will get that my 6 t h friend has 1 2 7 probability since it has the freedom to take birth only in any remaining 7 months.
Thus the probability of no one being born in same month is :
1 2 1 2 X 1 2 1 1 X 1 2 1 0 X 1 2 9 X 1 2 8 X 1 2 7
=0.222800925
=0.22 ( gave you in the directions )
Thus, the probability of finding two friends being born in the same month is 1 - 0.22
= 0 . 7 8