To convert the mixed number \( 5 \frac{3}{16} \) to a decimal using long division, follow these steps:
1. First, convert the mixed number to an improper fraction:
\[
5 \frac{3}{16} = \frac{(5 \times 16) + 3}{16} = \frac{80 + 3}{16} = \frac{83}{16}
\]
2. Now, perform long division by dividing 83 by 16.
- **16 goes into 83**:
- \( 16 \times 5 = 80 \) (Since \( 16 \times 6 = 96 \) which is too high)
- Write \( 5 \) above the division line.
3. Subtract \( 80 \) from \( 83 \):
\[
83 - 80 = 3
\]
4. Now, bring down a zero (since we want to convert to a decimal, we can add a decimal point and add a zero).
- Now we have \( 30 \).
5. **16 goes into 30**:
- \( 16 \times 1 = 16 \)
- Write \( 1 \) next to \( 5 \) above the division line.
6. Subtract \( 16 \) from \( 30 \):
\[
30 - 16 = 14
\]
7. Bring down another zero (making it \( 140 \)).
8. **16 goes into 140**:
- \( 16 \times 8 = 128 \)
- Write \( 8 \) next to \( 51 \).
9. Subtract \( 128 \) from \( 140 \):
\[
140 - 128 = 12
\]
10. Bring down another zero (making it \( 120 \)).
11. **16 goes into 120**:
- \( 16 \times 7 = 112 \)
- Write \( 7 \) next to the previous results.
12. Subtract \( 112 \) from \( 120 \):
\[
120 - 112 = 8
\]
13. Bring down another zero (making it \( 80 \)).
14. **16 goes into 80**:
- \( 16 \times 5 = 80 \)
- Write \( 5 \) next to the previous results.
15. Subtract \( 80 \) from \( 80 \) to get \( 0 \).
The result of the division gives us:
\[
83 \div 16 = 5.1875
\]
Thus, \( 5 \frac{3}{16} \) as a decimal is \( \textbf{5.1875} \).
The answer is:
**5.1875**.