Question 453200
The lengths of leaves of a plant are normally distributed with mean 5 inches and standard deviation .8inch. 
--------------------------------------
Approximately what percentage of leaves have a length between 4 inches and 6 inches? 
----
z(4) = (4-5)/0.8 = -10/8
z(6) = (6-5)/0.8 = 10/8
===============================
P(4 < x < 6) = P(-10/8 < z < 10/8) = 0.7887
===============================
Cheers,
Stan H.