Finding the Fourth Proportional to 139,287.15, 192,214.35 and 78,856.23

Step by Step Solution

1. Step 1: Write the proportion equation
   139,287.15 : 192,214.35 = 78,856.23 : x
2. Step 2: Convert to fraction form
   139,287.15/192,214.35 = 78,856.23/x
3. Step 3: Cross multiply
   139,287.15x = 192,214.35 × 78,856.23
4. Step 4: Simplify right side
   139,287.15x = 15,157,298,992.90
5. Step 5: Solve for x
   x = 15,157,298,992.90/139,287.15
6. Step 6: Final answer
   x = 108,820.51