1/ (-39) + 14 + 26 + 39
= [(-39) + 39] + (14 + 26)
= 0 + 40
= 40
2/ (-54) + 16 + (-6) + 54
= [(-54) + 54] + [16 + (-6)]
= 0 + 10
= 10
3/ 45 + 23 + (-35) + (-23)
= [45 + (-35)] + [23 + (-23)]
= 10 + 0
= 10
4/ 45. 17 – 5.9. 7
= 45. 17 – 45.7
= 45.(17 - 7)
= 45.10
= 450
5/ 24.(16 – 5) – 16. (24 - 5)
= 24.16 - 24.5 - 16.24 + 16.5
= (24.16 - 16.24) - (24.5 + 16.5)
= 0 - (24.5 + 16.5)
= -24.5 + 16.5
= 5.(-24 + 16)
= 5.(-8)
= -40