Finding the Fourth Proportional to 2,425.86, 3,639.15 and 865.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,425.86 : 3,639.15 = 865.42 : x
2. Step 2: Convert to fraction form
   2,425.86/3,639.15 = 865.42/x
3. Step 3: Cross multiply
   2,425.86x = 3,639.15 × 865.42
4. Step 4: Simplify right side
   2,425.86x = 3,149,384.10
5. Step 5: Solve for x
   x = 3,149,384.10/2,425.86
6. Step 6: Final answer
   x = 1,298.25