Finding the Fourth Proportional to 2,191.56, 3,287.83 and 959.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,191.56 : 3,287.83 = 959.31 : x
2. Step 2: Convert to fraction form
   2,191.56/3,287.83 = 959.31/x
3. Step 3: Cross multiply
   2,191.56x = 3,287.83 × 959.31
4. Step 4: Simplify right side
   2,191.56x = 3,154,048.20
5. Step 5: Solve for x
   x = 3,154,048.20/2,191.56
6. Step 6: Final answer
   x = 1,439.18