Finding the Fourth Proportional to 139,788, 192,920.40 and 80,172

Step by Step Solution

1. Step 1: Write the proportion equation
   139,788 : 192,920.40 = 80,172 : x
2. Step 2: Convert to fraction form
   139,788/192,920.40 = 80,172/x
3. Step 3: Cross multiply
   139,788x = 192,920.40 × 80,172
4. Step 4: Simplify right side
   139,788x = 15,466,814,308.80
5. Step 5: Solve for x
   x = 15,466,814,308.80/139,788
6. Step 6: Final answer
   x = 110,644.79