Finding the Fourth Proportional to 139,789, 192,921.78 and 80,173

Step by Step Solution

1. Step 1: Write the proportion equation
   139,789 : 192,921.78 = 80,173 : x
2. Step 2: Convert to fraction form
   139,789/192,921.78 = 80,173/x
3. Step 3: Cross multiply
   139,789x = 192,921.78 × 80,173
4. Step 4: Simplify right side
   139,789x = 15,467,117,867.94
5. Step 5: Solve for x
   x = 15,467,117,867.94/139,789
6. Step 6: Final answer
   x = 110,646.17