Finding the Third Proportional to 398,789 and 612,965.50

Step by Step Solution

1. Step 1: Write the proportion equation
   398,789 : 612,965.50 = 612,965.50 : x
2. Step 2: Convert to fraction form
   398,789/612,965.50 = 612,965.50/x
3. Step 3: Cross multiply
   398,789x = 612,965.50 × 612,965.50
4. Step 4: Simplify right side
   398,789x = 375,726,704,190.25
5. Step 5: Solve for x
   x = 375,726,704,190.25/398,789
6. Step 6: Final answer
   x = 942,169.18