Question

Tìm x

a,\(\dfrac{x}{5}\)=\(\dfrac{2}{10}\)         b,\(\dfrac{3}{5}\)x-\(\dfrac{1}{3}\)=\(\dfrac{1}{4}\)          c,\(\dfrac{1}{5}\):x=\(\dfrac{1}{5}\)-\(\dfrac{1}{7}\)

 

Answer 1

2/10 = 1/5

=> x = 1

3/5 x  = 1/4 + 1/3

3/5x = 7/12

x = 7/12 : 3/5

x = 35/36

1/5: x = 2/35

x = 1/5 : 2/35

x = 7/2

Answer 2

\(\dfrac{x}{5}=\dfrac{2}{10}\)

=> \(\dfrac{x}{5}=\dfrac{1}{5}\)

=> x=1

\(\dfrac{3}{5}x-\dfrac{1}{3}=\dfrac{1}{4}\)

=>\(\dfrac{3}{5}x=\dfrac{1}{4}+\dfrac{1}{3}\)

=>\(\dfrac{3}{5}x=\dfrac{7}{12}\)

=>   \(x=\dfrac{7}{12}:\dfrac{3}{5}\)

=>   x = \(\dfrac{35}{36}\)

\(\dfrac{1}{5}:x=\dfrac{1}{5}-\dfrac{1}{7}\)

=>\(\dfrac{1}{5}:x=\dfrac{2}{35}\)

=>        \(x=\dfrac{1}{5}:\dfrac{2}{35}\)

=>        \(x=\dfrac{7}{2}\)

Answer 3

\(a.x=\dfrac{5.2}{10}=1\\ b.x=\dfrac{3}{5}x=\dfrac{1}{4}+\dfrac{1}{3}=\dfrac{7}{12}\\ x=\dfrac{7}{12}:\dfrac{3}{5}=\dfrac{7}{12}.\dfrac{5}{3}=\dfrac{35}{36}\\ c.\dfrac{1}{5}:x=\dfrac{2}{35}\\ x=\dfrac{1}{5}:\dfrac{2}{35}=\dfrac{1}{5}.\dfrac{35}{2}=\dfrac{7}{2}\)

Answer 4

a, x/5 = 2/10

2x = 2

x = 2/2

x = 1

b, 3/5x - 1/3 = 1/4

3/5x = 1/4 + 1/3

3/5x = 7/12

x = 7/12 : 3/5

x = 7/12 . 5/3

x = 35/36

c, 1/5 : x = 1/5 - 1/7

1/5 : x = 2/35

x = 1/5 : 2/35

x = 1/5 . 35/2

x = 7/2

Answer 5

x = 7/2