Finding the Fourth Proportional to 1,399.14, 1,930.67 and 809.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.14 : 1,930.67 = 809.56 : x
2. Step 2: Convert to fraction form
   1,399.14/1,930.67 = 809.56/x
3. Step 3: Cross multiply
   1,399.14x = 1,930.67 × 809.56
4. Step 4: Simplify right side
   1,399.14x = 1,562,994.61
5. Step 5: Solve for x
   x = 1,562,994.61/1,399.14
6. Step 6: Final answer
   x = 1,117.11