Finding the Third Proportional to 5,576.50 and 8,639.75

Step by Step Solution

1. Step 1: Write the proportion equation
   5,576.50 : 8,639.75 = 8,639.75 : x
2. Step 2: Convert to fraction form
   5,576.50/8,639.75 = 8,639.75/x
3. Step 3: Cross multiply
   5,576.50x = 8,639.75 × 8,639.75
4. Step 4: Simplify right side
   5,576.50x = 74,645,280.06
5. Step 5: Solve for x
   x = 74,645,280.06/5,576.50
6. Step 6: Final answer
   x = 13,385.69