a) 23+{137 +[3 152–(248+594)–11]}
= 23+[137+(3 152-842-11)]
= 23+(137+2 321)
=23+2 458
=2481
b) (37+49) +[149 +(345+17+1 431)]
= 86 +(149+1 793)
=86+ 1 942
=2 028
c)
=267+( 3 479+ 256)
=267+3 735
=4 002
d)
=(4 643 +1 841+ 29) + 723
=6 513+ 723
=7 236
e)
=(3 279 +2 696 + 36) + 267
=6 011+267
=6 278
f)
=29+ [366+ (32+1 366+17)]
=29+ (366+ 1 415)
=29+ 1 781
=1 810
g)
=35+[489+17+(178+1 087-88)]
=35+(489+17+1 177)
=35+1 684
=1 718