Finding the Fourth Proportional to 12,900.31, 17,803.85 and 7,235.61

Step by Step Solution

1. Step 1: Write the proportion equation
   12,900.31 : 17,803.85 = 7,235.61 : x
2. Step 2: Convert to fraction form
   12,900.31/17,803.85 = 7,235.61/x
3. Step 3: Cross multiply
   12,900.31x = 17,803.85 × 7,235.61
4. Step 4: Simplify right side
   12,900.31x = 128,821,715.10
5. Step 5: Solve for x
   x = 128,821,715.10/12,900.31
6. Step 6: Final answer
   x = 9,985.94