Finding the Fourth Proportional to 2,086.66, 3,131.21 and 788.23

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.66 : 3,131.21 = 788.23 : x
2. Step 2: Convert to fraction form
   2,086.66/3,131.21 = 788.23/x
3. Step 3: Cross multiply
   2,086.66x = 3,131.21 × 788.23
4. Step 4: Simplify right side
   2,086.66x = 2,468,115.11
5. Step 5: Solve for x
   x = 2,468,115.11/2,086.66
6. Step 6: Final answer
   x = 1,182.81