Finding the Third Proportional to 638,743 and 1,390,886

Step by Step Solution

1. Step 1: Write the proportion equation
   638,743 : 1,390,886 = 1,390,886 : x
2. Step 2: Convert to fraction form
   638,743/1,390,886 = 1,390,886/x
3. Step 3: Cross multiply
   638,743x = 1,390,886 × 1,390,886
4. Step 4: Simplify right side
   638,743x = 1,934,563,864,996
5. Step 5: Solve for x
   x = 1,934,563,864,996/638,743
6. Step 6: Final answer
   x = 3,028,704.60