Finding the Fourth Proportional to 2,231.99, 3,080.57 and 1,288.39

Step by Step Solution

1. Step 1: Write the proportion equation
   2,231.99 : 3,080.57 = 1,288.39 : x
2. Step 2: Convert to fraction form
   2,231.99/3,080.57 = 1,288.39/x
3. Step 3: Cross multiply
   2,231.99x = 3,080.57 × 1,288.39
4. Step 4: Simplify right side
   2,231.99x = 3,968,978.09
5. Step 5: Solve for x
   x = 3,968,978.09/2,231.99
6. Step 6: Final answer
   x = 1,778.22