Finding the Fourth Proportional to 8,641, 12,889.67 and 8,498.31

Step by Step Solution

1. Step 1: Write the proportion equation
   8,641 : 12,889.67 = 8,498.31 : x
2. Step 2: Convert to fraction form
   8,641/12,889.67 = 8,498.31/x
3. Step 3: Cross multiply
   8,641x = 12,889.67 × 8,498.31
4. Step 4: Simplify right side
   8,641x = 109,540,411.46
5. Step 5: Solve for x
   x = 109,540,411.46/8,641
6. Step 6: Final answer
   x = 12,676.82