Finding the Fourth Proportional to 6,389.55, 8,817.75 and 3,872.10

Step by Step Solution

1. Step 1: Write the proportion equation
   6,389.55 : 8,817.75 = 3,872.10 : x
2. Step 2: Convert to fraction form
   6,389.55/8,817.75 = 3,872.10/x
3. Step 3: Cross multiply
   6,389.55x = 8,817.75 × 3,872.10
4. Step 4: Simplify right side
   6,389.55x = 34,143,209.78
5. Step 5: Solve for x
   x = 34,143,209.78/6,389.55
6. Step 6: Final answer
   x = 5,343.60