Đáp án:a)7−17
b)3011
c)=81
d)12−5
e)3−2
f)61
g)41
h)25
Giải thích các bước giải:
1a)145−27=145−1449=14−34=7−17
b)209−121=6027−605=622=3011
c)83−(43−21)=83−41=83−82
=81
d)3−2+43−21+61
=60−40+6045−6030+6010
=60−25=12−5
e)12−7−363=12−7−121=12−8=3−2
f)41−61+121=246−244+242
=244=61
g)101−12−1+151
=12012+12010+1208=12030=41
h)2327−21−5−234+2116+21
=(2327−233)+(215+2116)+21
=1+1+21=25
