Finding the Third Proportional to 257,949 and 398,587.50

Step by Step Solution

1. Step 1: Write the proportion equation
   257,949 : 398,587.50 = 398,587.50 : x
2. Step 2: Convert to fraction form
   257,949/398,587.50 = 398,587.50/x
3. Step 3: Cross multiply
   257,949x = 398,587.50 × 398,587.50
4. Step 4: Simplify right side
   257,949x = 158,871,995,156.25
5. Step 5: Solve for x
   x = 158,871,995,156.25/257,949
6. Step 6: Final answer
   x = 615,904.68