Finding the Third Proportional to 611,422 and 815,451

Step by Step Solution

1. Step 1: Write the proportion equation
   611,422 : 815,451 = 815,451 : x
2. Step 2: Convert to fraction form
   611,422/815,451 = 815,451/x
3. Step 3: Cross multiply
   611,422x = 815,451 × 815,451
4. Step 4: Simplify right side
   611,422x = 664,960,333,401
5. Step 5: Solve for x
   x = 664,960,333,401/611,422
6. Step 6: Final answer
   x = 1,087,563.64