Finding the Fourth Proportional to 139,147.50, 192,023.58 and 78,716.86

Step by Step Solution

1. Step 1: Write the proportion equation
   139,147.50 : 192,023.58 = 78,716.86 : x
2. Step 2: Convert to fraction form
   139,147.50/192,023.58 = 78,716.86/x
3. Step 3: Cross multiply
   139,147.50x = 192,023.58 × 78,716.86
4. Step 4: Simplify right side
   139,147.50x = 15,115,493,263.56
5. Step 5: Solve for x
   x = 15,115,493,263.56/139,147.50
6. Step 6: Final answer
   x = 108,629.28