Finding the Fourth Proportional to 18,086.72, 24,969.60 and 12,429.60

Step by Step Solution

1. Step 1: Write the proportion equation
   18,086.72 : 24,969.60 = 12,429.60 : x
2. Step 2: Convert to fraction form
   18,086.72/24,969.60 = 12,429.60/x
3. Step 3: Cross multiply
   18,086.72x = 24,969.60 × 12,429.60
4. Step 4: Simplify right side
   18,086.72x = 310,362,140.16
5. Step 5: Solve for x
   x = 310,362,140.16/18,086.72
6. Step 6: Final answer
   x = 17,159.67