Finding the Fourth Proportional to 10,425.20, 14,387.07 and 5,709.78

Step by Step Solution

1. Step 1: Write the proportion equation
   10,425.20 : 14,387.07 = 5,709.78 : x
2. Step 2: Convert to fraction form
   10,425.20/14,387.07 = 5,709.78/x
3. Step 3: Cross multiply
   10,425.20x = 14,387.07 × 5,709.78
4. Step 4: Simplify right side
   10,425.20x = 82,147,004.54
5. Step 5: Solve for x
   x = 82,147,004.54/10,425.20
6. Step 6: Final answer
   x = 7,879.66