Finding the Fourth Proportional to 1,022.81, 1,411.49 and 557.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,022.81 : 1,411.49 = 557.06 : x
2. Step 2: Convert to fraction form
   1,022.81/1,411.49 = 557.06/x
3. Step 3: Cross multiply
   1,022.81x = 1,411.49 × 557.06
4. Step 4: Simplify right side
   1,022.81x = 786,285.36
5. Step 5: Solve for x
   x = 786,285.36/1,022.81
6. Step 6: Final answer
   x = 768.75