Finding the Fourth Proportional to 20,684.39, 30,792.63 and 20,561.37

Step by Step Solution

1. Step 1: Write the proportion equation
   20,684.39 : 30,792.63 = 20,561.37 : x
2. Step 2: Convert to fraction form
   20,684.39/30,792.63 = 20,561.37/x
3. Step 3: Cross multiply
   20,684.39x = 30,792.63 × 20,561.37
4. Step 4: Simplify right side
   20,684.39x = 633,138,658.70
5. Step 5: Solve for x
   x = 633,138,658.70/20,684.39
6. Step 6: Final answer
   x = 30,609.50