Finding the Third Proportional to 642,640.50 and 1,399,558.50

Step by Step Solution

1. Step 1: Write the proportion equation
   642,640.50 : 1,399,558.50 = 1,399,558.50 : x
2. Step 2: Convert to fraction form
   642,640.50/1,399,558.50 = 1,399,558.50/x
3. Step 3: Cross multiply
   642,640.50x = 1,399,558.50 × 1,399,558.50
4. Step 4: Simplify right side
   642,640.50x = 1,958,763,994,922.25
5. Step 5: Solve for x
   x = 1,958,763,994,922.25/642,640.50
6. Step 6: Final answer
   x = 3,047,993.39