Finding the Fourth Proportional to 1,129.82, 1,559.29 and 687.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,129.82 : 1,559.29 = 687.79 : x
2. Step 2: Convert to fraction form
   1,129.82/1,559.29 = 687.79/x
3. Step 3: Cross multiply
   1,129.82x = 1,559.29 × 687.79
4. Step 4: Simplify right side
   1,129.82x = 1,072,456.27
5. Step 5: Solve for x
   x = 1,072,456.27/1,129.82
6. Step 6: Final answer
   x = 949.23