Finding the Fourth Proportional to 21,404.24, 29,531.16 and 12,908.96

Step by Step Solution

1. Step 1: Write the proportion equation
   21,404.24 : 29,531.16 = 12,908.96 : x
2. Step 2: Convert to fraction form
   21,404.24/29,531.16 = 12,908.96/x
3. Step 3: Cross multiply
   21,404.24x = 29,531.16 × 12,908.96
4. Step 4: Simplify right side
   21,404.24x = 381,216,637.02
5. Step 5: Solve for x
   x = 381,216,637.02/21,404.24
6. Step 6: Final answer
   x = 17,810.33