Đáp án:
a)|-123|+(-2015)+(-23)+|+2015|
= 123 - 2015 - 23 + 2015
= (123 - 23) + (-2015 + 2015)
= 100 + 0
= 100
b)-75 × |-47|-|+47| ×25
= -75 x (47 - 47) + 25
= 0 + 25
= 25
c)24 ×(31+14) - 31 ×(24-14)
= 24 x 45 - 31 x 10
= 1080 - 310
= 770
d)53 ×(-15)+(-15) ×47
= (-15)x(53 + 47)
= -15 x 100
= -1500
e)43 ×(53-81)+53 ×(81-43)
= 43 x (-28) + 53 x 38
= -1204 + 2014
= 810