Finding the Fourth Proportional to 39,815.59, 54,946.17 and 21,912.43

Step by Step Solution

1. Step 1: Write the proportion equation
   39,815.59 : 54,946.17 = 21,912.43 : x
2. Step 2: Convert to fraction form
   39,815.59/54,946.17 = 21,912.43/x
3. Step 3: Cross multiply
   39,815.59x = 54,946.17 × 21,912.43
4. Step 4: Simplify right side
   39,815.59x = 1,204,004,103.89
5. Step 5: Solve for x
   x = 1,204,004,103.89/39,815.59
6. Step 6: Final answer
   x = 30,239.51