Finding the Fourth Proportional to 8,139.36, 12,209.56 and 3,144.12

Step by Step Solution

1. Step 1: Write the proportion equation
   8,139.36 : 12,209.56 = 3,144.12 : x
2. Step 2: Convert to fraction form
   8,139.36/12,209.56 = 3,144.12/x
3. Step 3: Cross multiply
   8,139.36x = 12,209.56 × 3,144.12
4. Step 4: Simplify right side
   8,139.36x = 38,388,321.79
5. Step 5: Solve for x
   x = 38,388,321.79/8,139.36
6. Step 6: Final answer
   x = 4,716.38