Finding the Fourth Proportional to 31,105.35, 42,908.05 and 21,550.83

Step by Step Solution

1. Step 1: Write the proportion equation
   31,105.35 : 42,908.05 = 21,550.83 : x
2. Step 2: Convert to fraction form
   31,105.35/42,908.05 = 21,550.83/x
3. Step 3: Cross multiply
   31,105.35x = 42,908.05 × 21,550.83
4. Step 4: Simplify right side
   31,105.35x = 924,704,107.93
5. Step 5: Solve for x
   x = 924,704,107.93/31,105.35
6. Step 6: Final answer
   x = 29,728.14