Finding the Third Proportional to 289,404 and 620,338.50

Step by Step Solution

1. Step 1: Write the proportion equation
   289,404 : 620,338.50 = 620,338.50 : x
2. Step 2: Convert to fraction form
   289,404/620,338.50 = 620,338.50/x
3. Step 3: Cross multiply
   289,404x = 620,338.50 × 620,338.50
4. Step 4: Simplify right side
   289,404x = 384,819,854,582.25
5. Step 5: Solve for x
   x = 384,819,854,582.25/289,404
6. Step 6: Final answer
   x = 1,329,697.77