Finding the Fourth Proportional to 1,398.49, 1,930.28 and 809.37

Step by Step Solution

1. Step 1: Write the proportion equation
   1,398.49 : 1,930.28 = 809.37 : x
2. Step 2: Convert to fraction form
   1,398.49/1,930.28 = 809.37/x
3. Step 3: Cross multiply
   1,398.49x = 1,930.28 × 809.37
4. Step 4: Simplify right side
   1,398.49x = 1,562,310.72
5. Step 5: Solve for x
   x = 1,562,310.72/1,398.49
6. Step 6: Final answer
   x = 1,117.14