Finding the Third Proportional to 639,904 and 1,400,320

Step by Step Solution

1. Step 1: Write the proportion equation
   639,904 : 1,400,320 = 1,400,320 : x
2. Step 2: Convert to fraction form
   639,904/1,400,320 = 1,400,320/x
3. Step 3: Cross multiply
   639,904x = 1,400,320 × 1,400,320
4. Step 4: Simplify right side
   639,904x = 1,960,896,102,400
5. Step 5: Solve for x
   x = 1,960,896,102,400/639,904
6. Step 6: Final answer
   x = 3,064,359.81