Finding the Fourth Proportional to 1,209.31, 1,812.56 and 558.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.31 : 1,812.56 = 558.69 : x
2. Step 2: Convert to fraction form
   1,209.31/1,812.56 = 558.69/x
3. Step 3: Cross multiply
   1,209.31x = 1,812.56 × 558.69
4. Step 4: Simplify right side
   1,209.31x = 1,012,659.15
5. Step 5: Solve for x
   x = 1,012,659.15/1,209.31
6. Step 6: Final answer
   x = 837.39