Finding the Third Proportional to 643,874 and 1,398,556

Step by Step Solution

1. Step 1: Write the proportion equation
   643,874 : 1,398,556 = 1,398,556 : x
2. Step 2: Convert to fraction form
   643,874/1,398,556 = 1,398,556/x
3. Step 3: Cross multiply
   643,874x = 1,398,556 × 1,398,556
4. Step 4: Simplify right side
   643,874x = 1,955,958,885,136
5. Step 5: Solve for x
   x = 1,955,958,885,136/643,874
6. Step 6: Final answer
   x = 3,037,797.59