Finding the Third Proportional to 8,680 and 12,858

Step by Step Solution

1. Step 1: Write the proportion equation
   8,680 : 12,858 = 12,858 : x
2. Step 2: Convert to fraction form
   8,680/12,858 = 12,858/x
3. Step 3: Cross multiply
   8,680x = 12,858 × 12,858
4. Step 4: Simplify right side
   8,680x = 165,328,164
5. Step 5: Solve for x
   x = 165,328,164/8,680
6. Step 6: Final answer
   x = 19,047.02