5x230-7x(512:32+2/2 ) + 4687:43=
=1150-7x(16+1 ) + 109=
=1150-7x17 + 109=
=1150-119 + 109=
=1150-10=
=1140
b) (3^3 x 3 +2^45: 2^42 + ( 3^5 )^6 : 3^29 + 9^0) : 31 =
=(3^4 +2^3 + ( 3^30 : 3^29 + 1) : 31 =
=(81 +8 + 3 + 1) : 31 =
=93:31=3
c) 81^5 : 3^19 +31^10x 31^4 : 31^13 + 156 -792:72+(( 15^6)^4:3^23):5^22=
=3^20 : 3^19 +31^14 : 31^13 + 156-11+(( 3^24*5^24:3^23):5^22=
=3+31+156 -11+( 3*5^2)=
=34+156-11+75=254