Finding the Fourth Proportional to 1,379.59, 2,068.12 and 557.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.59 : 2,068.12 = 557.31 : x
2. Step 2: Convert to fraction form
   1,379.59/2,068.12 = 557.31/x
3. Step 3: Cross multiply
   1,379.59x = 2,068.12 × 557.31
4. Step 4: Simplify right side
   1,379.59x = 1,152,583.96
5. Step 5: Solve for x
   x = 1,152,583.96/1,379.59
6. Step 6: Final answer
   x = 835.45