Finding the Third Proportional to 643,988 and 1,398,595

Step by Step Solution

1. Step 1: Write the proportion equation
   643,988 : 1,398,595 = 1,398,595 : x
2. Step 2: Convert to fraction form
   643,988/1,398,595 = 1,398,595/x
3. Step 3: Cross multiply
   643,988x = 1,398,595 × 1,398,595
4. Step 4: Simplify right side
   643,988x = 1,956,067,974,025
5. Step 5: Solve for x
   x = 1,956,067,974,025/643,988
6. Step 6: Final answer
   x = 3,037,429.23