Finding the Third Proportional to 221,628 and 489,912

Step by Step Solution

1. Step 1: Write the proportion equation
   221,628 : 489,912 = 489,912 : x
2. Step 2: Convert to fraction form
   221,628/489,912 = 489,912/x
3. Step 3: Cross multiply
   221,628x = 489,912 × 489,912
4. Step 4: Simplify right side
   221,628x = 240,013,767,744
5. Step 5: Solve for x
   x = 240,013,767,744/221,628
6. Step 6: Final answer
   x = 1,082,957.78