Finding the Fourth Proportional to 13,144.68, 18,129.42 and 8,429.40

Step by Step Solution

1. Step 1: Write the proportion equation
   13,144.68 : 18,129.42 = 8,429.40 : x
2. Step 2: Convert to fraction form
   13,144.68/18,129.42 = 8,429.40/x
3. Step 3: Cross multiply
   13,144.68x = 18,129.42 × 8,429.40
4. Step 4: Simplify right side
   13,144.68x = 152,820,132.95
5. Step 5: Solve for x
   x = 152,820,132.95/13,144.68
6. Step 6: Final answer
   x = 11,626.01