Finding the Fourth Proportional to 1,207.89, 1,810.22 and 557.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,207.89 : 1,810.22 = 557.10 : x
2. Step 2: Convert to fraction form
   1,207.89/1,810.22 = 557.10/x
3. Step 3: Cross multiply
   1,207.89x = 1,810.22 × 557.10
4. Step 4: Simplify right side
   1,207.89x = 1,008,470.78
5. Step 5: Solve for x
   x = 1,008,470.78/1,207.89
6. Step 6: Final answer
   x = 834.90