Question

tìm x

Answer 1

\(a,15\times x=\dfrac{2}{5}\)

\(\Leftrightarrow x=\dfrac{2}{5}:15\)

\(\Leftrightarrow x=\dfrac{2}{5}\times\dfrac{1}{15}\)

\(\Leftrightarrow x=\dfrac{2}{75}\)

\(b,\dfrac{1}{8}:x=\dfrac{1}{2}\)

\(\Leftrightarrow x=\dfrac{1}{8}:\dfrac{1}{2}\)

\(\Leftrightarrow x=\dfrac{1}{8}\times2\)

\(\Leftrightarrow x=\dfrac{2}{8}\)

\(\Leftrightarrow x=\dfrac{1}{4}\)

Answer 2

a. => x = \(\dfrac{2}{5}\) : 15

=> x = \(\dfrac{2}{5}\)x \(\dfrac{1}{15}\)

=> x = \(\dfrac{2}{75}\)

b. x = \(\dfrac{1}{8}:\dfrac{1}{2}\)

=> x = \(\dfrac{1}{8}\) x 2

=> x = \(\dfrac{1}{4}\)

Answer 3

a, 15 x X = 2/5

            X = 15 x 2/5

            X =       6 

 

b, 1/8 : X = 1/2 

            x = 1/8 : 1/2 

            x =      2/8 = 1/4

Answer 4

a) 15 x \(x=\dfrac{2}{5}\) 

\(x=\dfrac{2}{5}:15\)

\(x=\dfrac{2}{75}\)

b) \(\dfrac{1}{8}:x=\dfrac{1}{2}\)

\(x=\dfrac{1}{8}:\dfrac{1}{2}\)

\(x=\dfrac{1}{4}\)