Finding the Third Proportional to 311,123 and 678,562

Step by Step Solution

1. Step 1: Write the proportion equation
   311,123 : 678,562 = 678,562 : x
2. Step 2: Convert to fraction form
   311,123/678,562 = 678,562/x
3. Step 3: Cross multiply
   311,123x = 678,562 × 678,562
4. Step 4: Simplify right side
   311,123x = 460,446,387,844
5. Step 5: Solve for x
   x = 460,446,387,844/311,123
6. Step 6: Final answer
   x = 1,479,949.69