Finding the Fourth Proportional to 15,139.12, 20,892.72 and 8,766.40

Step by Step Solution

1. Step 1: Write the proportion equation
   15,139.12 : 20,892.72 = 8,766.40 : x
2. Step 2: Convert to fraction form
   15,139.12/20,892.72 = 8,766.40/x
3. Step 3: Cross multiply
   15,139.12x = 20,892.72 × 8,766.40
4. Step 4: Simplify right side
   15,139.12x = 183,153,940.61
5. Step 5: Solve for x
   x = 183,153,940.61/15,139.12
6. Step 6: Final answer
   x = 12,098.06