Using the given figure,the ratio of $R_f$ values of sample $A$ and sample $C$ is $x \times 10^{-2}$. The value of $x$ is . . . . . . . .
Table: Paper chromatography of Samples
| Component | Distance from base line (cm) |
| :--- | :--- |
| Sample $A$ | $5.0$ |
| Sample $B$ | $6.5$ |
| Sample $C$ | $10.0$ |
| Solvent front | $12.5$ |

• A
  $50$
• B
  $40$
• C
  $30$
• D
  $20$