Finding the Third Proportional to 16,638 and 18,078

Step by Step Solution

1. Step 1: Write the proportion equation
   16,638 : 18,078 = 18,078 : x
2. Step 2: Convert to fraction form
   16,638/18,078 = 18,078/x
3. Step 3: Cross multiply
   16,638x = 18,078 × 18,078
4. Step 4: Simplify right side
   16,638x = 326,814,084
5. Step 5: Solve for x
   x = 326,814,084/16,638
6. Step 6: Final answer
   x = 19,642.63