Finding the Third Proportional to 256,055 and 387,618.50

Step by Step Solution

1. Step 1: Write the proportion equation
   256,055 : 387,618.50 = 387,618.50 : x
2. Step 2: Convert to fraction form
   256,055/387,618.50 = 387,618.50/x
3. Step 3: Cross multiply
   256,055x = 387,618.50 × 387,618.50
4. Step 4: Simplify right side
   256,055x = 150,248,101,542.25
5. Step 5: Solve for x
   x = 150,248,101,542.25/256,055
6. Step 6: Final answer
   x = 586,780.58