Finding the Third Proportional to 644,144 and 1,399,278

Step by Step Solution

1. Step 1: Write the proportion equation
   644,144 : 1,399,278 = 1,399,278 : x
2. Step 2: Convert to fraction form
   644,144/1,399,278 = 1,399,278/x
3. Step 3: Cross multiply
   644,144x = 1,399,278 × 1,399,278
4. Step 4: Simplify right side
   644,144x = 1,957,978,921,284
5. Step 5: Solve for x
   x = 1,957,978,921,284/644,144
6. Step 6: Final answer
   x = 3,039,660.26