Finding the Third Proportional to 431,636 and 677,111

Step by Step Solution

1. Step 1: Write the proportion equation
   431,636 : 677,111 = 677,111 : x
2. Step 2: Convert to fraction form
   431,636/677,111 = 677,111/x
3. Step 3: Cross multiply
   431,636x = 677,111 × 677,111
4. Step 4: Simplify right side
   431,636x = 458,479,306,321
5. Step 5: Solve for x
   x = 458,479,306,321/431,636
6. Step 6: Final answer
   x = 1,062,189.68