Finding the Fourth Proportional to 12,429.90, 17,163.63 and 8,256.78

Step by Step Solution

1. Step 1: Write the proportion equation
   12,429.90 : 17,163.63 = 8,256.78 : x
2. Step 2: Convert to fraction form
   12,429.90/17,163.63 = 8,256.78/x
3. Step 3: Cross multiply
   12,429.90x = 17,163.63 × 8,256.78
4. Step 4: Simplify right side
   12,429.90x = 141,716,316.91
5. Step 5: Solve for x
   x = 141,716,316.91/12,429.90
6. Step 6: Final answer
   x = 11,401.24