Bỏ dấu ngoặc rồi tính a) 159−524−59−424; b) 36+79+145−79−36; c) 334−117+234+42+117; d) 271−(−43)+271−(−17).

a) 159−524−59−424

=159−524−59+424

=159−59−524−424

=100−100=0

b) 36+79+145−79−36

=36+79+145−79−36

=36−36+79−79+145

=145

c) 334−117+234+42+117

=334−117−234+42+117

=334−234−117−117+42

=100+42=142

d) 271−(−43)+271−(−17)

=271−(−43)+271+17

=271+43−271−17

=271−271+43−17

=26