Finding the Third Proportional to 280,158.75 and 428,449.50

Step by Step Solution

1. Step 1: Write the proportion equation
   280,158.75 : 428,449.50 = 428,449.50 : x
2. Step 2: Convert to fraction form
   280,158.75/428,449.50 = 428,449.50/x
3. Step 3: Cross multiply
   280,158.75x = 428,449.50 × 428,449.50
4. Step 4: Simplify right side
   280,158.75x = 183,568,974,050.25
5. Step 5: Solve for x
   x = 183,568,974,050.25/280,158.75
6. Step 6: Final answer
   x = 655,231.99