Finding the Third Proportional to 12,156 and 18,321

Step by Step Solution

1. Step 1: Write the proportion equation
   12,156 : 18,321 = 18,321 : x
2. Step 2: Convert to fraction form
   12,156/18,321 = 18,321/x
3. Step 3: Cross multiply
   12,156x = 18,321 × 18,321
4. Step 4: Simplify right side
   12,156x = 335,659,041
5. Step 5: Solve for x
   x = 335,659,041/12,156
6. Step 6: Final answer
   x = 27,612.62