How many more troops did the IRA claim to have a total strength of then the number of troops that were actively engaged in fighting against the Crown?
return the  IRA ;return total strength in  troops  claimed of #1 ;return troops  actively engaged in  fighting against the  Crown of #1 ;return number of  #3 ;return the  difference of #2 and  #4
['select', 'project', 'project', 'aggregate', 'arithmetic']