1.
`a):`
`8 × (-75) + 150 + (-25) × 8`
`= −600+150−200`
`= −450−200`
`= −650`
`b):`
`(5 × 7 × 13)/(26 + 5 × 13)`
`= (35×13)/(26+5×13)`
`= 455/(26 + 5 × 13)`
`= 455/26+65`
`= 455/91`
`= 5`
`c):`
`(7/8 - 1/4 + 5/12) : 2(1)/2`
`= (7/8 - 2/8 + 5/12) : 2(1)/2`
`= (5/8 + 5/12) : 2(1)/2`
`= (15/24 + 10/24) : 2(1)/2`
`= 25/24 : 2(1)/2`
`= 25/24 : 5/2`
`= 25/24 × 2/5`
`= 50/120`
`= 5/12`
Note: Làm bài 1, xem bình luận.
Cho mình xin hay nhất nha bạn!!!!!
@Drew Mclntyre
