Finding the Third Proportional to 120,645 and 255,870

Step by Step Solution

1. Step 1: Write the proportion equation
   120,645 : 255,870 = 255,870 : x
2. Step 2: Convert to fraction form
   120,645/255,870 = 255,870/x
3. Step 3: Cross multiply
   120,645x = 255,870 × 255,870
4. Step 4: Simplify right side
   120,645x = 65,469,456,900
5. Step 5: Solve for x
   x = 65,469,456,900/120,645
6. Step 6: Final answer
   x = 542,662.00