Q: 111 (CAPF/2009)

If a © b is defined as ab + ba, then consider : I 2 © x = 100 II 4 © x = 145 III 3 © x = 145 IV 6 © x = 100 For which of the above, is x smallest ?
question_subject: 
History
question_year: 
2009
question_exam: 
CAPF
stats: 
0,24,80,32,32,16,24