Haggerty : Study in Arithmetic 



425 



6 



ATTEMPTS 



4 



RIGHTS 



T 



^ -I 

 I 



> J 



'60' 95 



iBOSTON 



tCITY 



T INDIVIDUAL 



tDETROIT 

 tCITY 



500 1000 1500 



FIG 2 MEDIANS GRADE 5 SERIES B SUBTR^ACTION 



500 1000 

 FIG. 3 MEDIANS GRADE S SERIE 



1500 

 MULTIPLICATION 



