Correct Answer - Option 2 :

\(\frac{y}{x +y}\)
**Explanation:**

**Dryness fraction:**

Dryness fraction (x) of steam is defined as the ratio of the mass of the dry steam to the total mass of both dry steam and liquid.

**\(x = \frac{{{m_g}}}{{{m_f} + {m_g}}}\;\left( {0 \le x \le 1} \right)\)**

where m_{g} = mass of the dry steam and m_{f} = mass of liquid

**Calculation:**

**Given:**

m_{g} = y, m_{f} = x

Dryness fraction = \(\frac {m_g}{m_f+m_g} = \frac {y}{x+y}\)