Finding the Third Proportional to 280,287 and 423,346.50

Step by Step Solution

1. Step 1: Write the proportion equation
   280,287 : 423,346.50 = 423,346.50 : x
2. Step 2: Convert to fraction form
   280,287/423,346.50 = 423,346.50/x
3. Step 3: Cross multiply
   280,287x = 423,346.50 × 423,346.50
4. Step 4: Simplify right side
   280,287x = 179,222,259,062.25
5. Step 5: Solve for x
   x = 179,222,259,062.25/280,287
6. Step 6: Final answer
   x = 639,424.09