Finding the Third Proportional to 280,399.50 and 423,944.50

Step by Step Solution

1. Step 1: Write the proportion equation
   280,399.50 : 423,944.50 = 423,944.50 : x
2. Step 2: Convert to fraction form
   280,399.50/423,944.50 = 423,944.50/x
3. Step 3: Cross multiply
   280,399.50x = 423,944.50 × 423,944.50
4. Step 4: Simplify right side
   280,399.50x = 179,728,939,080.25
5. Step 5: Solve for x
   x = 179,728,939,080.25/280,399.50
6. Step 6: Final answer
   x = 640,974.53