Finding the Fourth Proportional to 21,105.94, 31,658.31 and 8,622.43

Step by Step Solution

1. Step 1: Write the proportion equation
   21,105.94 : 31,658.31 = 8,622.43 : x
2. Step 2: Convert to fraction form
   21,105.94/31,658.31 = 8,622.43/x
3. Step 3: Cross multiply
   21,105.94x = 31,658.31 × 8,622.43
4. Step 4: Simplify right side
   21,105.94x = 272,971,561.89
5. Step 5: Solve for x
   x = 272,971,561.89/21,105.94
6. Step 6: Final answer
   x = 12,933.40