Question

[Nguyễn Dương Phương Linh]

 

20	=	12
41 - X		21

Answer 1

[Đoàn Ngọc Mai]

suy ra: 20 x 21 = 12 x ( 41- x)

           420 = 492 -12x

            12x= 492-420

            12x= 72

               x= 72 ;12

              x = 6
 vậy x=6

Answer 2

[Citii?]

\(\dfrac{20}{41-x}=\dfrac{12}{21}\)

\(41-x=20:\dfrac{12}{21}\)

\(41-x=20\times\dfrac{21}{12}\)

\(41-x=\dfrac{420}{12}\)

\(41-x=35\)

\(x=41-35\)

\(x=6\)

Vậy \(=6\)

Answer 3

[Ma Trần Viên Nguyên]

\(20\cdot21=12\cdot\left(41-x\right)\)

\(420=492-12x\)

\(12x=492-420\)

\(12x=72\)

\(x=72:12\)

\(x=6\)

Vậy: \(x=6\)