Finding the Fourth Proportional to 2,662.38, 3,993.71 and 813.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,662.38 : 3,993.71 = 813.56 : x
2. Step 2: Convert to fraction form
   2,662.38/3,993.71 = 813.56/x
3. Step 3: Cross multiply
   2,662.38x = 3,993.71 × 813.56
4. Step 4: Simplify right side
   2,662.38x = 3,249,098.67
5. Step 5: Solve for x
   x = 3,249,098.67/2,662.38
6. Step 6: Final answer
   x = 1,220.37