Finding the Fourth Proportional to 139,198.56, 192,091.32 and 78,768.09

Step by Step Solution

1. Step 1: Write the proportion equation
   139,198.56 : 192,091.32 = 78,768.09 : x
2. Step 2: Convert to fraction form
   139,198.56/192,091.32 = 78,768.09/x
3. Step 3: Cross multiply
   139,198.56x = 192,091.32 × 78,768.09
4. Step 4: Simplify right side
   139,198.56x = 15,130,666,381.98
5. Step 5: Solve for x
   x = 15,130,666,381.98/139,198.56
6. Step 6: Final answer
   x = 108,698.44