(1)1/4*(—8/9); (2)(—5/6)*(—3/10);
= =
= =
= =
(3)—2。4/15*25; (4)(—0。3)*(—1。3/7)。
= =
= =
= =
(1)1/4*(—8/9); (2)(—5/6)*(—3/10);
= =
= =
= =
(3)—2。4/15*25; (4)(—0。3)*(—1。3/7)。
= =
= =
= =
自己算
(1)
=—1/4*8/9
=—1*2/9
=—2/9
=—0.2222222222222222222222222222222222222222222222222222222222222222222222222222...
(2)
=5/6*3/10
=1/2*1/2
=1/4
=0.25
(3))—2。4/15*25;
=—(12/5/15)*25
=—4/25*25
=—4
(4)(—0。3)*(—1。3/7)。
=3/10 * (13/10/7)
=3/10 * 13/70
=39/700
=0.5571428571428572...
错了不管昂呵呵呵我向来不负责任