A. 8678(10) = 10000111100110(2) = 20746(8)=21E6(16)
B. 434(10) = 110110010(2) = 662(8) = 1B2(16)
C. 5565(10) = 1010110111101(2) = 12675(8) = 15BD(16)
A+B. 9112(10) = 10001110011000(2) = 21630(8) = 2398(16)
A-B. 8244(10) = 10000000110100(2) = 20064(8) = 2034(16)
A+C. 14243(10) = 11011110100011(2) = 33643(8) = 37A3(16)
A-C. 3113(10) = 110000101001(2) = 6051(8) = C29(16)