Finding the Fourth Proportional to 1,131.25, 1,561.35 and 689.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.25 : 1,561.35 = 689.08 : x
2. Step 2: Convert to fraction form
   1,131.25/1,561.35 = 689.08/x
3. Step 3: Cross multiply
   1,131.25x = 1,561.35 × 689.08
4. Step 4: Simplify right side
   1,131.25x = 1,075,895.06
5. Step 5: Solve for x
   x = 1,075,895.06/1,131.25
6. Step 6: Final answer
   x = 951.07