Finding the Fourth Proportional to 139,392.55, 209,005.78 and 55,164.68

Step by Step Solution

1. Step 1: Write the proportion equation
   139,392.55 : 209,005.78 = 55,164.68 : x
2. Step 2: Convert to fraction form
   139,392.55/209,005.78 = 55,164.68/x
3. Step 3: Cross multiply
   139,392.55x = 209,005.78 × 55,164.68
4. Step 4: Simplify right side
   139,392.55x = 11,529,737,635.43
5. Step 5: Solve for x
   x = 11,529,737,635.43/139,392.55
6. Step 6: Final answer
   x = 82,714.16