Finding the Fourth Proportional to 256,004.25, 383,991.99 and 78,510.78

Step by Step Solution

1. Step 1: Write the proportion equation
   256,004.25 : 383,991.99 = 78,510.78 : x
2. Step 2: Convert to fraction form
   256,004.25/383,991.99 = 78,510.78/x
3. Step 3: Cross multiply
   256,004.25x = 383,991.99 × 78,510.78
4. Step 4: Simplify right side
   256,004.25x = 30,147,510,648.65
5. Step 5: Solve for x
   x = 30,147,510,648.65/256,004.25
6. Step 6: Final answer
   x = 117,761.76