Finding the Fourth Proportional to 10,999.11, 16,476.31 and 8,781.69

Step by Step Solution

1. Step 1: Write the proportion equation
   10,999.11 : 16,476.31 = 8,781.69 : x
2. Step 2: Convert to fraction form
   10,999.11/16,476.31 = 8,781.69/x
3. Step 3: Cross multiply
   10,999.11x = 16,476.31 × 8,781.69
4. Step 4: Simplify right side
   10,999.11x = 144,689,846.76
5. Step 5: Solve for x
   x = 144,689,846.76/10,999.11
6. Step 6: Final answer
   x = 13,154.69