Finding the Fourth Proportional to 1,399.74, 1,932.06 and 810.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.74 : 1,932.06 = 810.54 : x
2. Step 2: Convert to fraction form
   1,399.74/1,932.06 = 810.54/x
3. Step 3: Cross multiply
   1,399.74x = 1,932.06 × 810.54
4. Step 4: Simplify right side
   1,399.74x = 1,566,011.91
5. Step 5: Solve for x
   x = 1,566,011.91/1,399.74
6. Step 6: Final answer
   x = 1,118.79