Finding the Fourth Proportional to 139,153.56, 192,018.78 and 78,716.76

Step by Step Solution

1. Step 1: Write the proportion equation
   139,153.56 : 192,018.78 = 78,716.76 : x
2. Step 2: Convert to fraction form
   139,153.56/192,018.78 = 78,716.76/x
3. Step 3: Cross multiply
   139,153.56x = 192,018.78 × 78,716.76
4. Step 4: Simplify right side
   139,153.56x = 15,115,096,220.75
5. Step 5: Solve for x
   x = 15,115,096,220.75/139,153.56
6. Step 6: Final answer
   x = 108,621.70