Finding the Fourth Proportional to 1,131.31, 1,559.86 and 1,069.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.31 : 1,559.86 = 1,069.75 : x
2. Step 2: Convert to fraction form
   1,131.31/1,559.86 = 1,069.75/x
3. Step 3: Cross multiply
   1,131.31x = 1,559.86 × 1,069.75
4. Step 4: Simplify right side
   1,131.31x = 1,668,660.24
5. Step 5: Solve for x
   x = 1,668,660.24/1,131.31
6. Step 6: Final answer
   x = 1,474.98