Finding the Fourth Proportional to 2,231.87, 3,079.88 and 1,287.83

Step by Step Solution

1. Step 1: Write the proportion equation
   2,231.87 : 3,079.88 = 1,287.83 : x
2. Step 2: Convert to fraction form
   2,231.87/3,079.88 = 1,287.83/x
3. Step 3: Cross multiply
   2,231.87x = 3,079.88 × 1,287.83
4. Step 4: Simplify right side
   2,231.87x = 3,966,361.86
5. Step 5: Solve for x
   x = 3,966,361.86/2,231.87
6. Step 6: Final answer
   x = 1,777.15