Finding the Third Proportional to 155,426 and 321,907

Step by Step Solution

1. Step 1: Write the proportion equation
   155,426 : 321,907 = 321,907 : x
2. Step 2: Convert to fraction form
   155,426/321,907 = 321,907/x
3. Step 3: Cross multiply
   155,426x = 321,907 × 321,907
4. Step 4: Simplify right side
   155,426x = 103,624,116,649
5. Step 5: Solve for x
   x = 103,624,116,649/155,426
6. Step 6: Final answer
   x = 666,710.31