Finding the Fourth Proportional to 139,408.30, 192,398.82 and 78,160.30

Step by Step Solution

1. Step 1: Write the proportion equation
   139,408.30 : 192,398.82 = 78,160.30 : x
2. Step 2: Convert to fraction form
   139,408.30/192,398.82 = 78,160.30/x
3. Step 3: Cross multiply
   139,408.30x = 192,398.82 × 78,160.30
4. Step 4: Simplify right side
   139,408.30x = 15,037,949,490.85
5. Step 5: Solve for x
   x = 15,037,949,490.85/139,408.30
6. Step 6: Final answer
   x = 107,869.83