Finding the Fourth Proportional to 860,676.10, 1,290,967.42 and 261,590.55

Step by Step Solution

1. Step 1: Write the proportion equation
   860,676.10 : 1,290,967.42 = 261,590.55 : x
2. Step 2: Convert to fraction form
   860,676.10/1,290,967.42 = 261,590.55/x
3. Step 3: Cross multiply
   860,676.10x = 1,290,967.42 × 261,590.55
4. Step 4: Simplify right side
   860,676.10x = 337,704,870,975.04
5. Step 5: Solve for x
   x = 337,704,870,975.04/860,676.10
6. Step 6: Final answer
   x = 392,371.62