Finding the Fourth Proportional to 860,279.76, 1,290,421.69 and 261,245.43

Step by Step Solution

1. Step 1: Write the proportion equation
   860,279.76 : 1,290,421.69 = 261,245.43 : x
2. Step 2: Convert to fraction form
   860,279.76/1,290,421.69 = 261,245.43/x
3. Step 3: Cross multiply
   860,279.76x = 1,290,421.69 × 261,245.43
4. Step 4: Simplify right side
   860,279.76x = 337,116,766,839.82
5. Step 5: Solve for x
   x = 337,116,766,839.82/860,279.76
6. Step 6: Final answer
   x = 391,868.76