Finding the Fourth Proportional to 12,997.89, 19,504.13 and 5,207.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,997.89 : 19,504.13 = 5,207.31 : x
2. Step 2: Convert to fraction form
   12,997.89/19,504.13 = 5,207.31/x
3. Step 3: Cross multiply
   12,997.89x = 19,504.13 × 5,207.31
4. Step 4: Simplify right side
   12,997.89x = 101,564,025.15
5. Step 5: Solve for x
   x = 101,564,025.15/12,997.89
6. Step 6: Final answer
   x = 7,813.89