Finding the Third Proportional to 306,768 and 641,722.50

Step by Step Solution

1. Step 1: Write the proportion equation
   306,768 : 641,722.50 = 641,722.50 : x
2. Step 2: Convert to fraction form
   306,768/641,722.50 = 641,722.50/x
3. Step 3: Cross multiply
   306,768x = 641,722.50 × 641,722.50
4. Step 4: Simplify right side
   306,768x = 411,807,767,006.25
5. Step 5: Solve for x
   x = 411,807,767,006.25/306,768
6. Step 6: Final answer
   x = 1,342,407.84