Finding the Fourth Proportional to 13,958.76, 20,910.72 and 8,103.12

Step by Step Solution

1. Step 1: Write the proportion equation
   13,958.76 : 20,910.72 = 8,103.12 : x
2. Step 2: Convert to fraction form
   13,958.76/20,910.72 = 8,103.12/x
3. Step 3: Cross multiply
   13,958.76x = 20,910.72 × 8,103.12
4. Step 4: Simplify right side
   13,958.76x = 169,442,073.45
5. Step 5: Solve for x
   x = 169,442,073.45/13,958.76
6. Step 6: Final answer
   x = 12,138.76