Finding the Third Proportional to 378,664 and 810,520.50

Step by Step Solution

1. Step 1: Write the proportion equation
   378,664 : 810,520.50 = 810,520.50 : x
2. Step 2: Convert to fraction form
   378,664/810,520.50 = 810,520.50/x
3. Step 3: Cross multiply
   378,664x = 810,520.50 × 810,520.50
4. Step 4: Simplify right side
   378,664x = 656,943,480,920.25
5. Step 5: Solve for x
   x = 656,943,480,920.25/378,664
6. Step 6: Final answer
   x = 1,734,898.17