Đáp án:
A) 8/3 . 2/5 . 3/8 . ( -10 )
= ( 8/3 . 3/8) . ( -10 . 2/5)
= 1 . ( -4 )
= -4.
B) 9/13 . -12/17 + 9/13 . 29/17
= 9/13 . ( -12/17 + 29/17 )
= 9/13 . 1
= 9/13.
C) 4/7 + 6/7 . 1/7 + 1/7 . 8/7
= 4/7 + 1/7 . ( 6/7 + 8/7)
= 4/7 + 1/7 . 2
= 4/7 + 2/7
= 6/7.