Finding the Fourth Proportional to 1,209.34, 1,812.59 and 558.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.34 : 1,812.59 = 558.71 : x
2. Step 2: Convert to fraction form
   1,209.34/1,812.59 = 558.71/x
3. Step 3: Cross multiply
   1,209.34x = 1,812.59 × 558.71
4. Step 4: Simplify right side
   1,209.34x = 1,012,702.40
5. Step 5: Solve for x
   x = 1,012,702.40/1,209.34
6. Step 6: Final answer
   x = 837.40