Finding the Fourth Proportional to 2,786.27, 4,178.72 and 811.37

Step by Step Solution

1. Step 1: Write the proportion equation
   2,786.27 : 4,178.72 = 811.37 : x
2. Step 2: Convert to fraction form
   2,786.27/4,178.72 = 811.37/x
3. Step 3: Cross multiply
   2,786.27x = 4,178.72 × 811.37
4. Step 4: Simplify right side
   2,786.27x = 3,390,463.10
5. Step 5: Solve for x
   x = 3,390,463.10/2,786.27
6. Step 6: Final answer
   x = 1,216.85