Finding the Fourth Proportional to 129,672.10, 178,940.59 and 72,317.31

Step by Step Solution

1. Step 1: Write the proportion equation
   129,672.10 : 178,940.59 = 72,317.31 : x
2. Step 2: Convert to fraction form
   129,672.10/178,940.59 = 72,317.31/x
3. Step 3: Cross multiply
   129,672.10x = 178,940.59 × 72,317.31
4. Step 4: Simplify right side
   129,672.10x = 12,940,502,118.61
5. Step 5: Solve for x
   x = 12,940,502,118.61/129,672.10
6. Step 6: Final answer
   x = 99,794.04