Finding the Third Proportional to 644,916 and 1,400,280

Step by Step Solution

1. Step 1: Write the proportion equation
   644,916 : 1,400,280 = 1,400,280 : x
2. Step 2: Convert to fraction form
   644,916/1,400,280 = 1,400,280/x
3. Step 3: Cross multiply
   644,916x = 1,400,280 × 1,400,280
4. Step 4: Simplify right side
   644,916x = 1,960,784,078,400
5. Step 5: Solve for x
   x = 1,960,784,078,400/644,916
6. Step 6: Final answer
   x = 3,040,371.27