Finding the Fourth Proportional to 139,813.92, 209,554.38 and 80,526.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139,813.92 : 209,554.38 = 80,526.78 : x
2. Step 2: Convert to fraction form
   139,813.92/209,554.38 = 80,526.78/x
3. Step 3: Cross multiply
   139,813.92x = 209,554.38 × 80,526.78
4. Step 4: Simplify right side
   139,813.92x = 16,874,739,456.30
5. Step 5: Solve for x
   x = 16,874,739,456.30/139,813.92
6. Step 6: Final answer
   x = 120,694.27