Finding the Third Proportional to 639,602 and 1,407,988

Step by Step Solution

1. Step 1: Write the proportion equation
   639,602 : 1,407,988 = 1,407,988 : x
2. Step 2: Convert to fraction form
   639,602/1,407,988 = 1,407,988/x
3. Step 3: Cross multiply
   639,602x = 1,407,988 × 1,407,988
4. Step 4: Simplify right side
   639,602x = 1,982,430,208,144
5. Step 5: Solve for x
   x = 1,982,430,208,144/639,602
6. Step 6: Final answer
   x = 3,099,474.69