Finding the Third Proportional to 639,465 and 1,362,640

Step by Step Solution

1. Step 1: Write the proportion equation
   639,465 : 1,362,640 = 1,362,640 : x
2. Step 2: Convert to fraction form
   639,465/1,362,640 = 1,362,640/x
3. Step 3: Cross multiply
   639,465x = 1,362,640 × 1,362,640
4. Step 4: Simplify right side
   639,465x = 1,856,787,769,600
5. Step 5: Solve for x
   x = 1,856,787,769,600/639,465
6. Step 6: Final answer
   x = 2,903,658.17