Finding the Fourth Proportional to 3,922.88, 5,401.72 and 3,390.81

Step by Step Solution

1. Step 1: Write the proportion equation
   3,922.88 : 5,401.72 = 3,390.81 : x
2. Step 2: Convert to fraction form
   3,922.88/5,401.72 = 3,390.81/x
3. Step 3: Cross multiply
   3,922.88x = 5,401.72 × 3,390.81
4. Step 4: Simplify right side
   3,922.88x = 18,316,179.18
5. Step 5: Solve for x
   x = 18,316,179.18/3,922.88
6. Step 6: Final answer
   x = 4,669.07