Finding the Fourth Proportional to 129,011.34, 178,025.82 and 72,411.78

Step by Step Solution

1. Step 1: Write the proportion equation
   129,011.34 : 178,025.82 = 72,411.78 : x
2. Step 2: Convert to fraction form
   129,011.34/178,025.82 = 72,411.78/x
3. Step 3: Cross multiply
   129,011.34x = 178,025.82 × 72,411.78
4. Step 4: Simplify right side
   129,011.34x = 12,891,166,512.16
5. Step 5: Solve for x
   x = 12,891,166,512.16/129,011.34
6. Step 6: Final answer
   x = 99,922.74