Finding the Third Proportional to 321,485.50 and 687,260

Step by Step Solution

1. Step 1: Write the proportion equation
   321,485.50 : 687,260 = 687,260 : x
2. Step 2: Convert to fraction form
   321,485.50/687,260 = 687,260/x
3. Step 3: Cross multiply
   321,485.50x = 687,260 × 687,260
4. Step 4: Simplify right side
   321,485.50x = 472,326,307,600
5. Step 5: Solve for x
   x = 472,326,307,600/321,485.50
6. Step 6: Final answer
   x = 1,469,199.41