Finding the Third Proportional to 128,117.25 and 280,260

Step by Step Solution

1. Step 1: Write the proportion equation
   128,117.25 : 280,260 = 280,260 : x
2. Step 2: Convert to fraction form
   128,117.25/280,260 = 280,260/x
3. Step 3: Cross multiply
   128,117.25x = 280,260 × 280,260
4. Step 4: Simplify right side
   128,117.25x = 78,545,667,600
5. Step 5: Solve for x
   x = 78,545,667,600/128,117.25
6. Step 6: Final answer
   x = 613,076.44