Finding the Third Proportional to 643,900 and 1,398,512

Step by Step Solution

1. Step 1: Write the proportion equation
   643,900 : 1,398,512 = 1,398,512 : x
2. Step 2: Convert to fraction form
   643,900/1,398,512 = 1,398,512/x
3. Step 3: Cross multiply
   643,900x = 1,398,512 × 1,398,512
4. Step 4: Simplify right side
   643,900x = 1,955,835,814,144
5. Step 5: Solve for x
   x = 1,955,835,814,144/643,900
6. Step 6: Final answer
   x = 3,037,483.79