Finding the Fourth Proportional to 1,280.52, 1,920.72 and 550.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,280.52 : 1,920.72 = 550.56 : x
2. Step 2: Convert to fraction form
   1,280.52/1,920.72 = 550.56/x
3. Step 3: Cross multiply
   1,280.52x = 1,920.72 × 550.56
4. Step 4: Simplify right side
   1,280.52x = 1,057,471.60
5. Step 5: Solve for x
   x = 1,057,471.60/1,280.52
6. Step 6: Final answer
   x = 825.81