Finding the Fourth Proportional to 12,405.38, 18,608.16 and 3,640.42

Step by Step Solution

1. Step 1: Write the proportion equation
   12,405.38 : 18,608.16 = 3,640.42 : x
2. Step 2: Convert to fraction form
   12,405.38/18,608.16 = 3,640.42/x
3. Step 3: Cross multiply
   12,405.38x = 18,608.16 × 3,640.42
4. Step 4: Simplify right side
   12,405.38x = 67,741,517.83
5. Step 5: Solve for x
   x = 67,741,517.83/12,405.38
6. Step 6: Final answer
   x = 5,460.66