Finding the Third Proportional to 312,914 and 642,415.50

Step by Step Solution

1. Step 1: Write the proportion equation
   312,914 : 642,415.50 = 642,415.50 : x
2. Step 2: Convert to fraction form
   312,914/642,415.50 = 642,415.50/x
3. Step 3: Cross multiply
   312,914x = 642,415.50 × 642,415.50
4. Step 4: Simplify right side
   312,914x = 412,697,674,640.25
5. Step 5: Solve for x
   x = 412,697,674,640.25/312,914
6. Step 6: Final answer
   x = 1,318,885.30