Finding the Fourth Proportional to 12,915.36, 19,378.17 and 5,519.61

Step by Step Solution

1. Step 1: Write the proportion equation
   12,915.36 : 19,378.17 = 5,519.61 : x
2. Step 2: Convert to fraction form
   12,915.36/19,378.17 = 5,519.61/x
3. Step 3: Cross multiply
   12,915.36x = 19,378.17 × 5,519.61
4. Step 4: Simplify right side
   12,915.36x = 106,959,940.91
5. Step 5: Solve for x
   x = 106,959,940.91/12,915.36
6. Step 6: Final answer
   x = 8,281.61