Finding the Third Proportional to 378,663.50 and 810,520

Step by Step Solution

1. Step 1: Write the proportion equation
   378,663.50 : 810,520 = 810,520 : x
2. Step 2: Convert to fraction form
   378,663.50/810,520 = 810,520/x
3. Step 3: Cross multiply
   378,663.50x = 810,520 × 810,520
4. Step 4: Simplify right side
   378,663.50x = 656,942,670,400
5. Step 5: Solve for x
   x = 656,942,670,400/378,663.50
6. Step 6: Final answer
   x = 1,734,898.32