document.write( "Question 460443: at a hospital maternity ward,
\n" ); document.write( " the hospital staff wants a probability distribution for the number of babies arriving each hour.
\n" ); document.write( "what is the probability exactly 7 babies are born during the next hour?
\n" ); document.write( "what is the probability than fewer than 3 babies are born during the next hour?
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Algebra.Com's Answer #315825 by Tatiana_Stebko(1539)\"\" \"About 
You can put this solution on YOUR website!
If the expected number of occurrences in this interval is a, then theprobability that there are exactly k occurrences is equal to
\n" ); document.write( "\"P%28k%2Ca+%29=%28%28a%5Ek%29e%5E%28-a%29%29%2Fk%21\", where
\n" ); document.write( "e is the base of the natural logarithm (e = 2.71828...)
\n" ); document.write( "k is the number of occurrences of an event — the probability of which is given by the function
\n" ); document.write( "k! is the factorial of k
\n" ); document.write( "a is a positive real number, equal to the expected number of occurrences during the given interval. \r
\n" ); document.write( "\n" ); document.write( "Babies arrive at an average of 8 babies per hour, so \"a=8\"
\n" ); document.write( "1) what is the probability exactly 7 babies are born during the next hour?
\n" ); document.write( "\"k=7\"
\n" ); document.write( "\"P%287%2C8+%29=%28%288%5E7%29e%5E%28-8%29%29%2F7%21=0.1396\"
\n" ); document.write( "2) what is the probability that fewer than 3 babies are born during the next hour?
\n" ); document.write( "Fewer than 3 - means that 0 babies (k=0) or 1 baby (k=1) or 2 babies (k=2) are born during the next hour
\n" ); document.write( "\"P%28fewer+than+3%29=P%280%2C8%29%2BP%281%2C8%29%2BP%282%2C8%29\"
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