Personal collections
Kestrels are birds whose adult wingspans are normally distributed with mean 
and standard deviation 
. A random sample of 120 adult kestrels is selected.
How many of these 120 adult kestrels would you expect to have wingspan between 
and 
?
The masses of adult kestrels are normally distributed with mean 
and standard deviation 
. It is known that 
of adult kestrels have mass greater than 
and 
have mass less than 
. Find the value of 
and the value of 
.
.
