Finding the Fourth Proportional to 3,921.22, 5,423.30 and 3,855.61

Step by Step Solution

1. Step 1: Write the proportion equation
   3,921.22 : 5,423.30 = 3,855.61 : x
2. Step 2: Convert to fraction form
   3,921.22/5,423.30 = 3,855.61/x
3. Step 3: Cross multiply
   3,921.22x = 5,423.30 × 3,855.61
4. Step 4: Simplify right side
   3,921.22x = 20,910,129.71
5. Step 5: Solve for x
   x = 20,910,129.71/3,921.22
6. Step 6: Final answer
   x = 5,332.56