Finding the Third Proportional to 280,299 and 423,364.50

Step by Step Solution

1. Step 1: Write the proportion equation
   280,299 : 423,364.50 = 423,364.50 : x
2. Step 2: Convert to fraction form
   280,299/423,364.50 = 423,364.50/x
3. Step 3: Cross multiply
   280,299x = 423,364.50 × 423,364.50
4. Step 4: Simplify right side
   280,299x = 179,237,499,860.25
5. Step 5: Solve for x
   x = 179,237,499,860.25/280,299
6. Step 6: Final answer
   x = 639,451.09