Finding the Fourth Proportional to 1,131.15, 1,560.48 and 689.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.15 : 1,560.48 = 689.03 : x
2. Step 2: Convert to fraction form
   1,131.15/1,560.48 = 689.03/x
3. Step 3: Cross multiply
   1,131.15x = 1,560.48 × 689.03
4. Step 4: Simplify right side
   1,131.15x = 1,075,209.73
5. Step 5: Solve for x
   x = 1,075,209.73/1,131.15
6. Step 6: Final answer
   x = 950.55