Finding the Third Proportional to 207,921 and 321,817.50

Step by Step Solution

1. Step 1: Write the proportion equation
   207,921 : 321,817.50 = 321,817.50 : x
2. Step 2: Convert to fraction form
   207,921/321,817.50 = 321,817.50/x
3. Step 3: Cross multiply
   207,921x = 321,817.50 × 321,817.50
4. Step 4: Simplify right side
   207,921x = 103,566,503,306.25
5. Step 5: Solve for x
   x = 103,566,503,306.25/207,921
6. Step 6: Final answer
   x = 498,105.07