Finding the Fourth Proportional to 10,815.10, 16,259.10 and 9,211.30

Step by Step Solution

1. Step 1: Write the proportion equation
   10,815.10 : 16,259.10 = 9,211.30 : x
2. Step 2: Convert to fraction form
   10,815.10/16,259.10 = 9,211.30/x
3. Step 3: Cross multiply
   10,815.10x = 16,259.10 × 9,211.30
4. Step 4: Simplify right side
   10,815.10x = 149,767,447.83
5. Step 5: Solve for x
   x = 149,767,447.83/10,815.10
6. Step 6: Final answer
   x = 13,847.99