Finding the Fourth Proportional to 258,662.40, 388,009.98 and 81,176.42

Step by Step Solution

1. Step 1: Write the proportion equation
   258,662.40 : 388,009.98 = 81,176.42 : x
2. Step 2: Convert to fraction form
   258,662.40/388,009.98 = 81,176.42/x
3. Step 3: Cross multiply
   258,662.40x = 388,009.98 × 81,176.42
4. Step 4: Simplify right side
   258,662.40x = 31,497,261,100.67
5. Step 5: Solve for x
   x = 31,497,261,100.67/258,662.40
6. Step 6: Final answer
   x = 121,769.77