Finding the Third Proportional to 678,828 and 1,340,520

Step by Step Solution

1. Step 1: Write the proportion equation
   678,828 : 1,340,520 = 1,340,520 : x
2. Step 2: Convert to fraction form
   678,828/1,340,520 = 1,340,520/x
3. Step 3: Cross multiply
   678,828x = 1,340,520 × 1,340,520
4. Step 4: Simplify right side
   678,828x = 1,796,993,870,400
5. Step 5: Solve for x
   x = 1,796,993,870,400/678,828
6. Step 6: Final answer
   x = 2,647,200.57