Finding the Fourth Proportional to 12,738.89, 19,088.85 and 5,339.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,738.89 : 19,088.85 = 5,339.31 : x
2. Step 2: Convert to fraction form
   12,738.89/19,088.85 = 5,339.31/x
3. Step 3: Cross multiply
   12,738.89x = 19,088.85 × 5,339.31
4. Step 4: Simplify right side
   12,738.89x = 101,921,313.47
5. Step 5: Solve for x
   x = 101,921,313.47/12,738.89
6. Step 6: Final answer
   x = 8,000.80