Finding the Fourth Proportional to 259,734.28, 389,599.37 and 139,847.39

Step by Step Solution

1. Step 1: Write the proportion equation
   259,734.28 : 389,599.37 = 139,847.39 : x
2. Step 2: Convert to fraction form
   259,734.28/389,599.37 = 139,847.39/x
3. Step 3: Cross multiply
   259,734.28x = 389,599.37 × 139,847.39
4. Step 4: Simplify right side
   259,734.28x = 54,484,456,569.83
5. Step 5: Solve for x
   x = 54,484,456,569.83/259,734.28
6. Step 6: Final answer
   x = 209,769.99