Finding the Fourth Proportional to 1,022.86, 1,411.52 and 557.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,022.86 : 1,411.52 = 557.10 : x
2. Step 2: Convert to fraction form
   1,022.86/1,411.52 = 557.10/x
3. Step 3: Cross multiply
   1,022.86x = 1,411.52 × 557.10
4. Step 4: Simplify right side
   1,022.86x = 786,357.79
5. Step 5: Solve for x
   x = 786,357.79/1,022.86
6. Step 6: Final answer
   x = 768.78