Finding the Fourth Proportional to 21,105.93, 29,126.48 and 12,155.03

Step by Step Solution

1. Step 1: Write the proportion equation
   21,105.93 : 29,126.48 = 12,155.03 : x
2. Step 2: Convert to fraction form
   21,105.93/29,126.48 = 12,155.03/x
3. Step 3: Cross multiply
   21,105.93x = 29,126.48 × 12,155.03
4. Step 4: Simplify right side
   21,105.93x = 354,033,031.79
5. Step 5: Solve for x
   x = 354,033,031.79/21,105.93
6. Step 6: Final answer
   x = 16,774.10