Finding the Third Proportional to 356,603.50 and 783,189.50

Step by Step Solution

1. Step 1: Write the proportion equation
   356,603.50 : 783,189.50 = 783,189.50 : x
2. Step 2: Convert to fraction form
   356,603.50/783,189.50 = 783,189.50/x
3. Step 3: Cross multiply
   356,603.50x = 783,189.50 × 783,189.50
4. Step 4: Simplify right side
   356,603.50x = 613,385,792,910.25
5. Step 5: Solve for x
   x = 613,385,792,910.25/356,603.50
6. Step 6: Final answer
   x = 1,720,077.88