Question

(x-2phan5) nhan 1phan2 =1

Answer 1

\(\left(x-\frac{2}{5}\right)×\frac{1}{2}=1=>\left(x-\frac{2}{5}\right)=1:\frac{1}{2}=>\left(x-\frac{2}{5}\right)=2=>x=2+\frac{2}{5}=>x=\frac{12}{5}\)

vậy \(x=\frac{12}{5}\)

Answer 2

             Bài làm :

Ta có :

\(\left(x-\frac{2}{5}\right)\times\frac{1}{2}=1\)

\(x-\frac{2}{5}=1\div\frac{1}{2}\)

\(x-\frac{2}{5}=2\)

\(x=2+\frac{2}{5}=2,4\)

Vậy x=2,4

Answer 3

= (x - 2/5) * 1/2 =1
=x- 2/5=1:1/2
=x -2/5= 2
=x       = 2 +2/5
=x       = 12/5

Answer 4

Bài làm :

\(\left(x-\frac{2}{5}\right)\times\frac{1}{2}=1\)

\(\Rightarrow x-\frac{2}{5}=1:\frac{1}{2}\)

\(\Rightarrow x-\frac{2}{5}=2\)

\(\Rightarrow x=2+\frac{2}{5}\)

\(\Rightarrow x=\frac{12}{5}\)

Vậy \(x=\frac{12}{5}\) .

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