Finding the Fourth Proportional to 12,222.39, 18,331.20 and 3,900.18

Step by Step Solution

1. Step 1: Write the proportion equation
   12,222.39 : 18,331.20 = 3,900.18 : x
2. Step 2: Convert to fraction form
   12,222.39/18,331.20 = 3,900.18/x
3. Step 3: Cross multiply
   12,222.39x = 18,331.20 × 3,900.18
4. Step 4: Simplify right side
   12,222.39x = 71,494,979.62
5. Step 5: Solve for x
   x = 71,494,979.62/12,222.39
6. Step 6: Final answer
   x = 5,849.51