Finding the Fourth Proportional to 139,300.83, 192,231.09 and 78,871.05

Step by Step Solution

1. Step 1: Write the proportion equation
   139,300.83 : 192,231.09 = 78,871.05 : x
2. Step 2: Convert to fraction form
   139,300.83/192,231.09 = 78,871.05/x
3. Step 3: Cross multiply
   139,300.83x = 192,231.09 × 78,871.05
4. Step 4: Simplify right side
   139,300.83x = 15,161,467,910.94
5. Step 5: Solve for x
   x = 15,161,467,910.94/139,300.83
6. Step 6: Final answer
   x = 108,839.75