Finding the Third Proportional to 769,128 and 1,638,336

Step by Step Solution

1. Step 1: Write the proportion equation
   769,128 : 1,638,336 = 1,638,336 : x
2. Step 2: Convert to fraction form
   769,128/1,638,336 = 1,638,336/x
3. Step 3: Cross multiply
   769,128x = 1,638,336 × 1,638,336
4. Step 4: Simplify right side
   769,128x = 2,684,144,848,896
5. Step 5: Solve for x
   x = 2,684,144,848,896/769,128
6. Step 6: Final answer
   x = 3,489,854.55