Finding the Third Proportional to 645,420 and 1,399,704

Step by Step Solution

1. Step 1: Write the proportion equation
   645,420 : 1,399,704 = 1,399,704 : x
2. Step 2: Convert to fraction form
   645,420/1,399,704 = 1,399,704/x
3. Step 3: Cross multiply
   645,420x = 1,399,704 × 1,399,704
4. Step 4: Simplify right side
   645,420x = 1,959,171,287,616
5. Step 5: Solve for x
   x = 1,959,171,287,616/645,420
6. Step 6: Final answer
   x = 3,035,498.26