Finding the Fourth Proportional to 139,150.98, 192,028.32 and 78,720.39

Step by Step Solution

1. Step 1: Write the proportion equation
   139,150.98 : 192,028.32 = 78,720.39 : x
2. Step 2: Convert to fraction form
   139,150.98/192,028.32 = 78,720.39/x
3. Step 3: Cross multiply
   139,150.98x = 192,028.32 × 78,720.39
4. Step 4: Simplify right side
   139,150.98x = 15,116,544,241.44
5. Step 5: Solve for x
   x = 15,116,544,241.44/139,150.98
6. Step 6: Final answer
   x = 108,634.12