计算:(1)49 24 25 ×(-5) ;(2)(-8)×(-7.2)×(-2.5)× 5 12 ;(3)-7

2025-04-08 06:55:30
推荐回答(1个)
回答1:

(1)49
24
25
×(-5)

=(50-
1
25
)×(-5),
=-249
4
5

(2)(-8)×(-7.2)×(-2.5)×
5
12

=-(8×
36
5
×
5
2
×
5
12
),
=-60;
(3)-7.8×(-8.1)×0×|-19.6|=0;
(4)-|-0.25|×(-5)×4×(-
1
25
),
=-0.25×(-5)×4×(-
1
25
),
=-
1
5