b. 4.25 – 12.5 + 170:10
= 100 - 60 +17
= 40 + 17
= 47
c. 369 - (206 – 15)-(-206+ 369)
= 369 - 206 + 15+ 206 - 369
= 163+15 + 206 - 369
=  178 + 206 - 369
= 384 - 369
= 15
d. 345 – 150:[(3^3 – 24)^2 – (-21)]+2016^0
= 345 – 150:[(27 – 24)^2 – (-21)]+1
= 345 – 150:[3^2 +21]+1
= 345 – 150:[9 +21]+1
= 345 – 150:30+1
= 345 – 5+1
= 340+1
= 341
e. (-12).(7- 72)- 25.(55- 43)
= (-12).(-65)- 25.(12)
= 780-(-300)
= 780+300
=1080
f. (39 – 19):(-2) + (34 – 22).5
= 20:(-2) + 12.5
= (-10) + 60
= 50
g. 25.(-2)^2 + 5.(2+3)
= 25.4 + 5.5
= 100 + 25
= 125
h. {2^3 + [1+ (3 – 1)^2]}:13
= {8 + [1+ 2^2]}:13
= {8 + [1+ 4]}:13
= {8 + 5}:13
= 13:13
=1
i. 33.(17 – 5) – 17.(33 – 5)
= 33.12 – 17.28
= 396 – 476
= (-80)