a) 160 - ( 8 . 52 - 6 . 52 )
= 160 - 52 . (8 - 6 )
= 160 - 52 . 2
= 160 - 25 . 2
= 160 - 50
= 110
b) 4 . 25 - ( 25 )7 : ( 24 )8
= 100 - 235 : 232
= 100 - 23
= 100 - 8
= 92
c) 5871 . [ 928 - 165 . 5 ]
= 5871 . [ 928 - 825 ]
= 5871 . 103
= 604 713
d) 111 + 111 = 222