Finding the Fourth Proportional to 6,431.91, 8,869.52 and 3,911.57

Step by Step Solution

1. Step 1: Write the proportion equation
   6,431.91 : 8,869.52 = 3,911.57 : x
2. Step 2: Convert to fraction form
   6,431.91/8,869.52 = 3,911.57/x
3. Step 3: Cross multiply
   6,431.91x = 8,869.52 × 3,911.57
4. Step 4: Simplify right side
   6,431.91x = 34,693,713.78
5. Step 5: Solve for x
   x = 34,693,713.78/6,431.91
6. Step 6: Final answer
   x = 5,394.00