Finding the Fourth Proportional to 8,139.98, 12,210.88 and 2,591.99

Step by Step Solution

1. Step 1: Write the proportion equation
   8,139.98 : 12,210.88 = 2,591.99 : x
2. Step 2: Convert to fraction form
   8,139.98/12,210.88 = 2,591.99/x
3. Step 3: Cross multiply
   8,139.98x = 12,210.88 × 2,591.99
4. Step 4: Simplify right side
   8,139.98x = 31,650,411.32
5. Step 5: Solve for x
   x = 31,650,411.32/8,139.98
6. Step 6: Final answer
   x = 3,888.27