Finding the Fourth Proportional to 21,669.57, 29,905.39 and 12,109.48

Step by Step Solution

1. Step 1: Write the proportion equation
   21,669.57 : 29,905.39 = 12,109.48 : x
2. Step 2: Convert to fraction form
   21,669.57/29,905.39 = 12,109.48/x
3. Step 3: Cross multiply
   21,669.57x = 29,905.39 × 12,109.48
4. Step 4: Simplify right side
   21,669.57x = 362,138,722.10
5. Step 5: Solve for x
   x = 362,138,722.10/21,669.57
6. Step 6: Final answer
   x = 16,711.86