Đáp án:a)700
b)2000
c)123
d)134
Giải thích các bước giải:
a)$143+539+257+261-500=(143+257)+(539+261)-500=400+800-500=700$
b)$29·34+66·29-900=29(34+66)-900=29·100-900=2000$
c)$120-85:(2^{5}-15)+2^{3}=120-85:17+8=120-5+8=123$
d)$560:7+[150-(17·2^{3}-2^{3}·5)]=80+[150-2^{3}(17-5)]=80+(150-8·12)=80+54=134$