Finding the Third Proportional to 728,070 and 1,139,638

Step by Step Solution

1. Step 1: Write the proportion equation
   728,070 : 1,139,638 = 1,139,638 : x
2. Step 2: Convert to fraction form
   728,070/1,139,638 = 1,139,638/x
3. Step 3: Cross multiply
   728,070x = 1,139,638 × 1,139,638
4. Step 4: Simplify right side
   728,070x = 1,298,774,771,044
5. Step 5: Solve for x
   x = 1,298,774,771,044/728,070
6. Step 6: Final answer
   x = 1,783,859.75