Finding the Fourth Proportional to 409,123.31, 613,724.61 and 139,441.61

Step by Step Solution

1. Step 1: Write the proportion equation
   409,123.31 : 613,724.61 = 139,441.61 : x
2. Step 2: Convert to fraction form
   409,123.31/613,724.61 = 139,441.61/x
3. Step 3: Cross multiply
   409,123.31x = 613,724.61 × 139,441.61
4. Step 4: Simplify right side
   409,123.31x = 85,578,747,715.02
5. Step 5: Solve for x
   x = 85,578,747,715.02/409,123.31
6. Step 6: Final answer
   x = 209,175.93