Finding the Fourth Proportional to 1,439.27, 1,986.12 and 809.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,439.27 : 1,986.12 = 809.83 : x
2. Step 2: Convert to fraction form
   1,439.27/1,986.12 = 809.83/x
3. Step 3: Cross multiply
   1,439.27x = 1,986.12 × 809.83
4. Step 4: Simplify right side
   1,439.27x = 1,608,422.04
5. Step 5: Solve for x
   x = 1,608,422.04/1,439.27
6. Step 6: Final answer
   x = 1,117.53