Finding the Third Proportional to 865.69 and 1,144.76

Step by Step Solution

1. Step 1: Write the proportion equation
   865.69 : 1,144.76 = 1,144.76 : x
2. Step 2: Convert to fraction form
   865.69/1,144.76 = 1,144.76/x
3. Step 3: Cross multiply
   865.69x = 1,144.76 × 1,144.76
4. Step 4: Simplify right side
   865.69x = 1,310,470.45
5. Step 5: Solve for x
   x = 1,310,470.45/865.69
6. Step 6: Final answer
   x = 1,513.79