Finding the Third Proportional to 684,678 and 1,390,089

Step by Step Solution

1. Step 1: Write the proportion equation
   684,678 : 1,390,089 = 1,390,089 : x
2. Step 2: Convert to fraction form
   684,678/1,390,089 = 1,390,089/x
3. Step 3: Cross multiply
   684,678x = 1,390,089 × 1,390,089
4. Step 4: Simplify right side
   684,678x = 1,932,347,427,921
5. Step 5: Solve for x
   x = 1,932,347,427,921/684,678
6. Step 6: Final answer
   x = 2,822,271.82