Finding the Fourth Proportional to 21,204.24, 29,241.72 and 12,705.12

Step by Step Solution

1. Step 1: Write the proportion equation
   21,204.24 : 29,241.72 = 12,705.12 : x
2. Step 2: Convert to fraction form
   21,204.24/29,241.72 = 12,705.12/x
3. Step 3: Cross multiply
   21,204.24x = 29,241.72 × 12,705.12
4. Step 4: Simplify right side
   21,204.24x = 371,519,561.61
5. Step 5: Solve for x
   x = 371,519,561.61/21,204.24
6. Step 6: Final answer
   x = 17,521.00