Finding the Fourth Proportional to 21,709.31, 29,960.28 and 12,150.09

Step by Step Solution

1. Step 1: Write the proportion equation
   21,709.31 : 29,960.28 = 12,150.09 : x
2. Step 2: Convert to fraction form
   21,709.31/29,960.28 = 12,150.09/x
3. Step 3: Cross multiply
   21,709.31x = 29,960.28 × 12,150.09
4. Step 4: Simplify right side
   21,709.31x = 364,020,098.43
5. Step 5: Solve for x
   x = 364,020,098.43/21,709.31
6. Step 6: Final answer
   x = 16,767.93