Finding the Third Proportional to 311,105.25 and 664,856.25

Step by Step Solution

1. Step 1: Write the proportion equation
   311,105.25 : 664,856.25 = 664,856.25 : x
2. Step 2: Convert to fraction form
   311,105.25/664,856.25 = 664,856.25/x
3. Step 3: Cross multiply
   311,105.25x = 664,856.25 × 664,856.25
4. Step 4: Simplify right side
   311,105.25x = 442,033,833,164.06
5. Step 5: Solve for x
   x = 442,033,833,164.06/311,105.25
6. Step 6: Final answer
   x = 1,420,849.80