Finding the Third Proportional to 412,980 and 638,296.50

Step by Step Solution

1. Step 1: Write the proportion equation
   412,980 : 638,296.50 = 638,296.50 : x
2. Step 2: Convert to fraction form
   412,980/638,296.50 = 638,296.50/x
3. Step 3: Cross multiply
   412,980x = 638,296.50 × 638,296.50
4. Step 4: Simplify right side
   412,980x = 407,422,421,912.25
5. Step 5: Solve for x
   x = 407,422,421,912.25/412,980
6. Step 6: Final answer
   x = 986,542.74