Finding the Third Proportional to 102,111 and 209,406

Step by Step Solution

1. Step 1: Write the proportion equation
   102,111 : 209,406 = 209,406 : x
2. Step 2: Convert to fraction form
   102,111/209,406 = 209,406/x
3. Step 3: Cross multiply
   102,111x = 209,406 × 209,406
4. Step 4: Simplify right side
   102,111x = 43,850,872,836
5. Step 5: Solve for x
   x = 43,850,872,836/102,111
6. Step 6: Final answer
   x = 429,443.18