If x, 2, 10 and y are in proportion, the values of x and y are respectively :

1. 0.2 and 0.25

2. 0.2 and 50

3. 0.4 and 50

4. 0.4 and 25

Given,

x, 2, 10 and y are in proportion.

$\therefore \dfrac{x}{2} = \dfrac{2}{10} = \dfrac{10}{y}$ …….(1)

Considering L.H.S. of the equation (1) :

$\Rightarrow \dfrac{x}{2} = \dfrac{2}{10} \\[1em] \Rightarrow x = \dfrac{2 \times 2}{10} \\[1em] \Rightarrow x = \dfrac{4}{10} = 0.4$

Considering R.H.S. of the equation (1) :

$\Rightarrow \dfrac{2}{10} = \dfrac{10}{y} \\[1em] \Rightarrow y = \dfrac{10 \times 10}{2} \\[1em] \Rightarrow y = \dfrac{100}{2} \\[1em] \Rightarrow y = 50.$

Hence, Option 3 is the correct option.