Finding the Fourth Proportional to 1,308.83, 1,805.90 and 811.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.83 : 1,805.90 = 811.49 : x
2. Step 2: Convert to fraction form
   1,308.83/1,805.90 = 811.49/x
3. Step 3: Cross multiply
   1,308.83x = 1,805.90 × 811.49
4. Step 4: Simplify right side
   1,308.83x = 1,465,456.70
5. Step 5: Solve for x
   x = 1,465,456.70/1,308.83
6. Step 6: Final answer
   x = 1,119.67