Finding the Fourth Proportional to 11,500.15, 15,886.15 and 8,880.61

Step by Step Solution

1. Step 1: Write the proportion equation
   11,500.15 : 15,886.15 = 8,880.61 : x
2. Step 2: Convert to fraction form
   11,500.15/15,886.15 = 8,880.61/x
3. Step 3: Cross multiply
   11,500.15x = 15,886.15 × 8,880.61
4. Step 4: Simplify right side
   11,500.15x = 141,078,702.55
5. Step 5: Solve for x
   x = 141,078,702.55/11,500.15
6. Step 6: Final answer
   x = 12,267.55