a) = 7x 16 - 81: 9 + 39
= 112 - 9 + 39
= 14
b) = -1562 \(-\)(-1002)
= -560
c) = 2018.( 123+78 -1)
= 2018 x 200
= 403600
a) 7 . 42 - 81 : 32 + |-39|
= 7 . 16 - 81 : 9 + 39
= 112 - 9 + 39
= 103 + 39 = 142
b) [456 + (-2018)] - (360 - 2018 + 456)
= 456 + (-2018) - 360 + 2018 - 456
= (456 - 456) + (-2018 + 2018) - 360
= 0 + 0 - 360 = -360
c) 2018 . 123 + 78 . 2018 - 2018
= 2018 . (123 + 78 - 1)
= 2018 . 200 = 403600