Finding the Third Proportional to 6,858 and 12,108

Step by Step Solution

1. Step 1: Write the proportion equation
   6,858 : 12,108 = 12,108 : x
2. Step 2: Convert to fraction form
   6,858/12,108 = 12,108/x
3. Step 3: Cross multiply
   6,858x = 12,108 × 12,108
4. Step 4: Simplify right side
   6,858x = 146,603,664
5. Step 5: Solve for x
   x = 146,603,664/6,858
6. Step 6: Final answer
   x = 21,377.03