One mole of an ideal monoatomic gas $\left(\gamma =\frac{5}{3}\right)$ is mixed with one mole of diatomic gas $\left(\gamma =\frac{7}{5}\right)$. The value of $\gamma$ for the mixture is (where, $\gamma$ represents the ratio of specific heat capacities at constant pressure and constant volume)

• Correct answer
  A

  $1.5$
• B

  $1.75$
• C

  $1.33$
• D

  $1.85$

Hence, the correct answer is option: 'A'.