Finding the Third Proportional to 212,805 and 321,745.50

Step by Step Solution

1. Step 1: Write the proportion equation
   212,805 : 321,745.50 = 321,745.50 : x
2. Step 2: Convert to fraction form
   212,805/321,745.50 = 321,745.50/x
3. Step 3: Cross multiply
   212,805x = 321,745.50 × 321,745.50
4. Step 4: Simplify right side
   212,805x = 103,520,166,770.25
5. Step 5: Solve for x
   x = 103,520,166,770.25/212,805
6. Step 6: Final answer
   x = 486,455.52