Finding the Third Proportional to 8,112 and 12,216

Step by Step Solution

1. Step 1: Write the proportion equation
   8,112 : 12,216 = 12,216 : x
2. Step 2: Convert to fraction form
   8,112/12,216 = 12,216/x
3. Step 3: Cross multiply
   8,112x = 12,216 × 12,216
4. Step 4: Simplify right side
   8,112x = 149,230,656
5. Step 5: Solve for x
   x = 149,230,656/8,112
6. Step 6: Final answer
   x = 18,396.28