Finding the Third Proportional to 12,640 and 16,056

Step by Step Solution

1. Step 1: Write the proportion equation
   12,640 : 16,056 = 16,056 : x
2. Step 2: Convert to fraction form
   12,640/16,056 = 16,056/x
3. Step 3: Cross multiply
   12,640x = 16,056 × 16,056
4. Step 4: Simplify right side
   12,640x = 257,795,136
5. Step 5: Solve for x
   x = 257,795,136/12,640
6. Step 6: Final answer
   x = 20,395.18