Finding the Third Proportional to 381,336 and 728,040

Step by Step Solution

1. Step 1: Write the proportion equation
   381,336 : 728,040 = 728,040 : x
2. Step 2: Convert to fraction form
   381,336/728,040 = 728,040/x
3. Step 3: Cross multiply
   381,336x = 728,040 × 728,040
4. Step 4: Simplify right side
   381,336x = 530,042,241,600
5. Step 5: Solve for x
   x = 530,042,241,600/381,336
6. Step 6: Final answer
   x = 1,389,961.19