Finding the Third Proportional to 12,388 and 16,422

Step by Step Solution

1. Step 1: Write the proportion equation
   12,388 : 16,422 = 16,422 : x
2. Step 2: Convert to fraction form
   12,388/16,422 = 16,422/x
3. Step 3: Cross multiply
   12,388x = 16,422 × 16,422
4. Step 4: Simplify right side
   12,388x = 269,682,084
5. Step 5: Solve for x
   x = 269,682,084/12,388
6. Step 6: Final answer
   x = 21,769.62