Question

Answer 1

Bài `3`

`7,6 : 1,9 . x= 3,2`

`<=> 4.x= 3,2`

`<=> x= 3,2 :4`

`<=>x= 0,8`

`-----------`

`(x-15).3: 12=6`

`<=> (x-15).3= 16 . 12`

`<=> (x-15).3= 192`

`<=>x-15= 192 : 3`

`<=>x-15= 64`

`<=> x= 64 +15`

`<=>x= 79`

`----------`

`(x:4+6).7=70`

`<=> x:4+6= 70:7`

`<=> x:4+6= 10`

`<=> x: 4= 10+6`

`<=> x: 4= 16`

`<=> x= 16 . 4`

`<=>x= 64`

Answer 2

a) 7,6 : 1,9 . x = 3,2 <=> 4x = 3,2 <=> x = 0,8

b) (x - 15).3 : 12 = 6 <=> 3(x - 15) = 72 <=> x - 15 = 24 <=> x = 39

c) *sai đề?*