Finding the Fourth Proportional to 9,123.30, 13,676.85 and 8,139.15

Step by Step Solution

1. Step 1: Write the proportion equation
   9,123.30 : 13,676.85 = 8,139.15 : x
2. Step 2: Convert to fraction form
   9,123.30/13,676.85 = 8,139.15/x
3. Step 3: Cross multiply
   9,123.30x = 13,676.85 × 8,139.15
4. Step 4: Simplify right side
   9,123.30x = 111,317,933.68
5. Step 5: Solve for x
   x = 111,317,933.68/9,123.30
6. Step 6: Final answer
   x = 12,201.50