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BELL SYSTEM TECHNICAL JOURNAL 



the "per cent gain over the efficiency of x + y trunks" if the total 

 gx + y trunks are placed in a single complete-access group. A few 

 problems will make clear the exact meaning and use of the curves. 



01 23 4-5678 



TOTAL TRUNKS IN MULTIPLES OF (x + y) 



Fig. 8 — -Graded multiple efficiency, .x + y = 10. P = 0.01. 



Suppose we wish to know how much load may be submitted to each 

 subgroup of a symmetrical graded multiple of 105 trunks having five 

 commons out of an access of 30, such that, on the average, one call in 



40 

 + 36 



X 



li. 32 

 O 



T) 28 



20 

 cr 



O 16 



Z 



rf 12 



I 2 3 4 5 6 



TOTAL TRUNKS IN MULTIPLES OF (x + y) 



Fig. 9 — Graded multiple efficiency, .v + y = 20. P = 0.01. 



