Finding the Fourth Proportional to 21,105.24, 29,120.76 and 12,605.10

Step by Step Solution

1. Step 1: Write the proportion equation
   21,105.24 : 29,120.76 = 12,605.10 : x
2. Step 2: Convert to fraction form
   21,105.24/29,120.76 = 12,605.10/x
3. Step 3: Cross multiply
   21,105.24x = 29,120.76 × 12,605.10
4. Step 4: Simplify right side
   21,105.24x = 367,070,091.88
5. Step 5: Solve for x
   x = 367,070,091.88/21,105.24
6. Step 6: Final answer
   x = 17,392.37