Finding the Third Proportional to 401,931 and 639,796.50

Step by Step Solution

1. Step 1: Write the proportion equation
   401,931 : 639,796.50 = 639,796.50 : x
2. Step 2: Convert to fraction form
   401,931/639,796.50 = 639,796.50/x
3. Step 3: Cross multiply
   401,931x = 639,796.50 × 639,796.50
4. Step 4: Simplify right side
   401,931x = 409,339,561,412.25
5. Step 5: Solve for x
   x = 409,339,561,412.25/401,931
6. Step 6: Final answer
   x = 1,018,432.42