Finding the Fourth Proportional to 21,080.98, 29,081.79 and 12,578.23

Step by Step Solution

1. Step 1: Write the proportion equation
   21,080.98 : 29,081.79 = 12,578.23 : x
2. Step 2: Convert to fraction form
   21,080.98/29,081.79 = 12,578.23/x
3. Step 3: Cross multiply
   21,080.98x = 29,081.79 × 12,578.23
4. Step 4: Simplify right side
   21,080.98x = 365,797,443.43
5. Step 5: Solve for x
   x = 365,797,443.43/21,080.98
6. Step 6: Final answer
   x = 17,352.01