Finding the Fourth Proportional to 2,662.16, 3,993.69 and 813.23

Step by Step Solution

1. Step 1: Write the proportion equation
   2,662.16 : 3,993.69 = 813.23 : x
2. Step 2: Convert to fraction form
   2,662.16/3,993.69 = 813.23/x
3. Step 3: Cross multiply
   2,662.16x = 3,993.69 × 813.23
4. Step 4: Simplify right side
   2,662.16x = 3,247,768.55
5. Step 5: Solve for x
   x = 3,247,768.55/2,662.16
6. Step 6: Final answer
   x = 1,219.98