274 COLLECTION OF STATISTICS. 



be greater, equal or smaller than the actual area, according to 

 the size of the standard quality : 



Reduced A = 



The reduced areas of the several parts are obtained b} r the 

 inverse proportion of their qualities to the standard quality; 

 thus : 



Reduced a l 

 Reduced a = 



etc. 



Example, as above : Let the standard quality = 50 c, then 

 Total reduced area = 



200 x 60 + 100 x 50+200 x 40+500 x 30_ ftnn 



- ouu acies, 



ou 



and for the several blocks : 



50 



= acres 



(3 ) 



200x40 



Total . . 800 acres. 



800 

 Reduced area of annual coupe = - = 80 acres, 



and the size of coupes in the several blocks : 



(1) 60 : 50 = 80 :# and a? = ^~= 66'67 



ou 



(2) 50: 50 = 80 ix = = SO'OO 



50 



