Question

tìm x 

a) x : 10 + x 3,9 =6

b)X x 8,25 - x : 4 = 3

c)1,5 :4,5 x X =2,5

Answer 1

 dấu j v bn ?

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`b)` 

`x xx  8,25 - x : 4 = 3`

`x xx 8,25 - x xx 1/4 = 3`

`x xx (8,25 - 1/4) = 3`

`x xx (33/4 - 1/4)=3`

`x xx 32/4 = 3`

`x xx 8 = 3`

`x=  3 : 8`

`x=3/8`

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`c)`

`1,5 : 4,5 xx x = 2,5`

`3/2 : 9/2 xx x = 5/2`

`3/2 xx 2/9 xx x  = 5/2`

`1/3 xx x = 5/2`

`x=5/2 : 1/3`

`x=5/2 xx 3`

`x=15/2`