Finding the Third Proportional to 311,439 and 679,156.50

Step by Step Solution

1. Step 1: Write the proportion equation
   311,439 : 679,156.50 = 679,156.50 : x
2. Step 2: Convert to fraction form
   311,439/679,156.50 = 679,156.50/x
3. Step 3: Cross multiply
   311,439x = 679,156.50 × 679,156.50
4. Step 4: Simplify right side
   311,439x = 461,253,551,492.25
5. Step 5: Solve for x
   x = 461,253,551,492.25/311,439
6. Step 6: Final answer
   x = 1,481,039.79