Finding the Fourth Proportional to 8,580.12, 12,869.56 and 5,621.59

Step by Step Solution

1. Step 1: Write the proportion equation
   8,580.12 : 12,869.56 = 5,621.59 : x
2. Step 2: Convert to fraction form
   8,580.12/12,869.56 = 5,621.59/x
3. Step 3: Cross multiply
   8,580.12x = 12,869.56 × 5,621.59
4. Step 4: Simplify right side
   8,580.12x = 72,347,389.80
5. Step 5: Solve for x
   x = 72,347,389.80/8,580.12
6. Step 6: Final answer
   x = 8,431.98