Finding the Third Proportional to 8,640 and 12,654

Step by Step Solution

1. Step 1: Write the proportion equation
   8,640 : 12,654 = 12,654 : x
2. Step 2: Convert to fraction form
   8,640/12,654 = 12,654/x
3. Step 3: Cross multiply
   8,640x = 12,654 × 12,654
4. Step 4: Simplify right side
   8,640x = 160,123,716
5. Step 5: Solve for x
   x = 160,123,716/8,640
6. Step 6: Final answer
   x = 18,532.84