Finding the Third Proportional to 411.50 and 863.50

Step by Step Solution

1. Step 1: Write the proportion equation
   411.50 : 863.50 = 863.50 : x
2. Step 2: Convert to fraction form
   411.50/863.50 = 863.50/x
3. Step 3: Cross multiply
   411.50x = 863.50 × 863.50
4. Step 4: Simplify right side
   411.50x = 745,632.25
5. Step 5: Solve for x
   x = 745,632.25/411.50
6. Step 6: Final answer
   x = 1,811.99