Finding the Third Proportional to 139,764 and 221,418

Step by Step Solution

1. Step 1: Write the proportion equation
   139,764 : 221,418 = 221,418 : x
2. Step 2: Convert to fraction form
   139,764/221,418 = 221,418/x
3. Step 3: Cross multiply
   139,764x = 221,418 × 221,418
4. Step 4: Simplify right side
   139,764x = 49,025,930,724
5. Step 5: Solve for x
   x = 49,025,930,724/139,764
6. Step 6: Final answer
   x = 350,776.53