Finding the Fourth Proportional to 6,453.60, 8,909.28 and 4,218.72

Step by Step Solution

1. Step 1: Write the proportion equation
   6,453.60 : 8,909.28 = 4,218.72 : x
2. Step 2: Convert to fraction form
   6,453.60/8,909.28 = 4,218.72/x
3. Step 3: Cross multiply
   6,453.60x = 8,909.28 × 4,218.72
4. Step 4: Simplify right side
   6,453.60x = 37,585,757.72
5. Step 5: Solve for x
   x = 37,585,757.72/6,453.60
6. Step 6: Final answer
   x = 5,824.00