Finding the Third Proportional to 8,666.25 and 12,871.50

Step by Step Solution

1. Step 1: Write the proportion equation
   8,666.25 : 12,871.50 = 12,871.50 : x
2. Step 2: Convert to fraction form
   8,666.25/12,871.50 = 12,871.50/x
3. Step 3: Cross multiply
   8,666.25x = 12,871.50 × 12,871.50
4. Step 4: Simplify right side
   8,666.25x = 165,675,512.25
5. Step 5: Solve for x
   x = 165,675,512.25/8,666.25
6. Step 6: Final answer
   x = 19,117.32