Finding the Third Proportional to 128,048 and 280,488

Step by Step Solution

1. Step 1: Write the proportion equation
   128,048 : 280,488 = 280,488 : x
2. Step 2: Convert to fraction form
   128,048/280,488 = 280,488/x
3. Step 3: Cross multiply
   128,048x = 280,488 × 280,488
4. Step 4: Simplify right side
   128,048x = 78,673,518,144
5. Step 5: Solve for x
   x = 78,673,518,144/128,048
6. Step 6: Final answer
   x = 614,406.46