For example if the first field is 10, the second is 5 and the third is 3, they should get the error message. the second and third added together should match the first..what is wrong???

IF( The_number_of_Enrollment_Mtgs_Requested__c   = How_many_enrollment_mtgs_did_VMC_conduct__c +  How_many_meetings_did_others_conduct__c   , The_number_of_Enrollment_Mtgs_Requested__c   = How_many_enrollment_mtgs_did_VMC_conduct__c  +  How_many_meetings_did_others_conduct__c ,  The_number_of_Enrollment_Mtgs_Requested__c    >    How_many_enrollment_mtgs_did_VMC_conduct__c +  How_many_meetings_did_others_conduct__c )