The correct answer is: $0.625$
Explanation
We convert the fraction $\tfrac{5}{8}$ to a decimal.
Steps:
- Multiply numerator and denominator by $125$ to get a denominator of $1000$:
$$\frac{5}{8}=\frac{5\times125}{8\times125}=\frac{625}{1000}$$
- Convert $\tfrac{625}{1000}$ to a decimal:
$$\frac{625}{1000}=0.625$$
Therefore, $\tfrac{5}{8}=0.625$.