Finding the Third Proportional to 128,942.25 and 280,301.25

Step by Step Solution

1. Step 1: Write the proportion equation
   128,942.25 : 280,301.25 = 280,301.25 : x
2. Step 2: Convert to fraction form
   128,942.25/280,301.25 = 280,301.25/x
3. Step 3: Cross multiply
   128,942.25x = 280,301.25 × 280,301.25
4. Step 4: Simplify right side
   128,942.25x = 78,568,790,751.56
5. Step 5: Solve for x
   x = 78,568,790,751.56/128,942.25
6. Step 6: Final answer
   x = 609,333.18