Finding the Fourth Proportional to 6,419.05, 8,857.33 and 3,899.83

Step by Step Solution

1. Step 1: Write the proportion equation
   6,419.05 : 8,857.33 = 3,899.83 : x
2. Step 2: Convert to fraction form
   6,419.05/8,857.33 = 3,899.83/x
3. Step 3: Cross multiply
   6,419.05x = 8,857.33 × 3,899.83
4. Step 4: Simplify right side
   6,419.05x = 34,542,081.25
5. Step 5: Solve for x
   x = 34,542,081.25/6,419.05
6. Step 6: Final answer
   x = 5,381.18