Finding the Third Proportional to 638,604 and 1,399,680

Step by Step Solution

1. Step 1: Write the proportion equation
   638,604 : 1,399,680 = 1,399,680 : x
2. Step 2: Convert to fraction form
   638,604/1,399,680 = 1,399,680/x
3. Step 3: Cross multiply
   638,604x = 1,399,680 × 1,399,680
4. Step 4: Simplify right side
   638,604x = 1,959,104,102,400
5. Step 5: Solve for x
   x = 1,959,104,102,400/638,604
6. Step 6: Final answer
   x = 3,067,791.78