Finding the Fourth Proportional to 1,379.31, 2,067.59 and 558.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.31 : 2,067.59 = 558.05 : x
2. Step 2: Convert to fraction form
   1,379.31/2,067.59 = 558.05/x
3. Step 3: Cross multiply
   1,379.31x = 2,067.59 × 558.05
4. Step 4: Simplify right side
   1,379.31x = 1,153,805.47
5. Step 5: Solve for x
   x = 1,153,805.47/1,379.31
6. Step 6: Final answer
   x = 836.51