a) 4 . 13 . 25
= ( 4 . 25 ) . 13
= 100 . 13
= 1300
b) 113 + 25 + 887
= ( 113 + 887 ) + 25
= 1000 + 25
= 1025
c) ( 529 : 525 ) . 5
= 54 . 5
= 55
4 . 13 . 25 = 13 . 25 .4
= 13 . 100
= 1300
113 + 25 + 887 = (113 + 887) + 25
= 1000 + 25
= 1025
\(\left(5^{29}:5^{25}\right).5=5^4.5\)
\(=5^{4+1}\)
\(=5^5\)
Học tốt!