Finding the Third Proportional to 12,128 and 16,216

Step by Step Solution

1. Step 1: Write the proportion equation
   12,128 : 16,216 = 16,216 : x
2. Step 2: Convert to fraction form
   12,128/16,216 = 16,216/x
3. Step 3: Cross multiply
   12,128x = 16,216 × 16,216
4. Step 4: Simplify right side
   12,128x = 262,958,656
5. Step 5: Solve for x
   x = 262,958,656/12,128
6. Step 6: Final answer
   x = 21,681.95