Finding the Fourth Proportional to 21,105.54, 29,130.48 and 12,158.22

Step by Step Solution

1. Step 1: Write the proportion equation
   21,105.54 : 29,130.48 = 12,158.22 : x
2. Step 2: Convert to fraction form
   21,105.54/29,130.48 = 12,158.22/x
3. Step 3: Cross multiply
   21,105.54x = 29,130.48 × 12,158.22
4. Step 4: Simplify right side
   21,105.54x = 354,174,784.55
5. Step 5: Solve for x
   x = 354,174,784.55/21,105.54
6. Step 6: Final answer
   x = 16,781.13