Finding the Third Proportional to 16,906 and 21,810

Step by Step Solution

1. Step 1: Write the proportion equation
   16,906 : 21,810 = 21,810 : x
2. Step 2: Convert to fraction form
   16,906/21,810 = 21,810/x
3. Step 3: Cross multiply
   16,906x = 21,810 × 21,810
4. Step 4: Simplify right side
   16,906x = 475,676,100
5. Step 5: Solve for x
   x = 475,676,100/16,906
6. Step 6: Final answer
   x = 28,136.53