Finding the Third Proportional to 435,362 and 638,139

Step by Step Solution

1. Step 1: Write the proportion equation
   435,362 : 638,139 = 638,139 : x
2. Step 2: Convert to fraction form
   435,362/638,139 = 638,139/x
3. Step 3: Cross multiply
   435,362x = 638,139 × 638,139
4. Step 4: Simplify right side
   435,362x = 407,221,383,321
5. Step 5: Solve for x
   x = 407,221,383,321/435,362
6. Step 6: Final answer
   x = 935,362.72