c) 108(12 + 13 ) + 25 . 92
= 2700 + 2300
= 5000
d) 2.169.12 - 3.68.8 - 24
= ( 2 .12 ) . 169 - (3.8) . 68 - 24
= 24 . 169 - 24 . 68 - 24
= 24(169 - 68 ) - 24
= 2424 - 24 = 2400
e) 2.56.24 - 3.36.16 + 4.12.95 + 6.3.8.5
= ( 2 . 24 ) . 56 - ( 3.16 ) . 36 + (4.12) .95 + (6.8) . 3 . 5
= 48 . 56 - 48 . 36 + 48 . 95 + 48 . 15
= 48(56 - 36 + 95 + 15 )
= 6240
c) 108.12+25.92+13.108
=(108+12)+(25.13)+(108+92)
=120+325+200
=645